CN109408416B

CN109408416B - Address mapping table entry page management method and device

Info

Publication number: CN109408416B
Application number: CN201811099080.5A
Authority: CN
Inventors: 唐侃毅
Original assignee: Hangzhou H3C Technologies Co Ltd
Current assignee: Hangzhou H3C Technologies Co Ltd
Priority date: 2018-09-20
Filing date: 2018-09-20
Publication date: 2021-01-26
Anticipated expiration: 2038-09-20
Also published as: CN109408416A; WO2020057479A1

Abstract

The application provides a method and a device for managing address mapping table entry pages, comprising the following steps: after the equipment is started, reading all address mapping table entry pages in the hard disk of the equipment into a cache of the equipment for recording; when the data stored in the device is updated, updating an address mapping table entry page corresponding to the updated data in the cache; determining each updated address mapping table entry page and the corresponding updating times thereof in all address mapping table entry pages recorded in the cache; and determining the designated address mapping table item pages to be issued meeting the issuing conditions according to the updating times of the designated address mapping table item pages, issuing the designated address mapping table item pages to the hard disk of the equipment to update the address mapping table item pages stored in the hard disk, and issuing the first sub-mapping table corresponding to the updated address mapping table to the hard disk when the equipment is abnormally powered off. By using the method provided by the application, the space loss caused by updating the address mapping table entry page to the hard disk can be reduced, and the data reading speed of the hard disk is accelerated.

Description

Address mapping table entry page management method and device

Technical Field

The present application relates to the field of storage, and in particular, to a method and an apparatus for managing address mapping table entry pages.

Background

Solid State Disk (Solid State Disk) is a new generation of storage device. The storage medium of the solid state disk adopts a solid state flash memory medium to replace the traditional magnetic medium. Because the flash memory medium is a nonvolatile storage medium with high integration level and ultra-large capacity, compared with a magnetic medium, the flash memory medium has great improvement in the aspects of read-write speed, read-write delay, shock resistance safety, power consumption and the like.

However, flash memory media also have some disadvantages, for example, flash memory does not support overwrite, i.e., new data cannot be continuously written to the storage space of stored data to overwrite the stored data. Therefore, when one of the address mapping table entry pages stored in the solid state disk is updated, the updated address mapping table entry page needs to be written into a new storage space, and the updated mapping table entry page cannot be covered by the updated mapping table in the storage space occupied by the address mapping table entry page. In particular, when a large number of entries in the address mapping entry page are updated in sequence, a large number of new storage spaces are required to store the address mapping entry page after each entry update in sequence. For example, after the entry 1 in the address mapping entry page is updated, a new storage space needs to be applied to store the address mapping entry page after the entry 1 is updated, and then, the entry 2 in the address mapping entry page is also updated, another new storage space needs to be applied to store the address mapping entry page after the entry 2 is updated, which greatly wastes the storage space of the solid state disk.

Disclosure of Invention

In view of the above, the present application provides a method and an apparatus for managing an address mapping table entry page, so as to save a storage space of a hard disk when the address mapping table entry page in the hard disk is updated.

Specifically, the method is realized through the following technical scheme:

according to a first aspect of the present application, there is provided an address mapping table entry page management method, which is applied to a storage device, and includes:

after the equipment is started, reading all address mapping table entry pages in the hard disk of the equipment into a cache of the equipment for recording;

when the data stored in the device is updated, updating an address mapping table entry page corresponding to the updated data in the cache;

determining at least one updated designated address mapping table entry page and the corresponding updating times of each designated address mapping table entry page in all address mapping table entry pages recorded in the cache;

and determining the designated address mapping table entry pages to be issued meeting the issuing conditions according to the updating times of the designated address mapping table entry pages, and issuing the designated address mapping table entry pages to the hard disk of the equipment so as to update the address mapping table entry pages stored in the hard disk.

Optionally, the determining, according to the number of updates of each designated address mapping, a to-be-issued designated address mapping table entry page that meets the issue condition and issues the to-be-issued designated address mapping table entry page to the hard disk of the device includes:

taking the specified address mapping table entry page with the updating times larger than a preset updating time threshold as a specified address mapping table entry page to be issued, and issuing the specified address mapping table entry page to a hard disk of the equipment;

alternatively, the first and second electrodes may be,

when the total number of all the appointed address mapping table item pages is larger than a first number threshold value, taking the first N appointed address mapping table item pages with the largest updating times as appointed address mapping table item pages to be issued to a hard disk of the equipment, so that the total number of the appointed address mapping table item pages in the issued cache is smaller than a second number threshold value; wherein the second quantity threshold is less than the first quantity threshold; n is an integer greater than zero.

Optionally, the determining at least one updated specified address mapping table entry page and the number of updates corresponding to each specified address mapping table entry page includes:

searching updating times variables respectively corresponding to all address mapping table entry pages;

determining the address mapping table entry page with the updating time variable value larger than the initial value as the specified address mapping table entry page;

and determining the updating times of the specified address mapping table entry page according to the variable value of the corresponding updating times of the specified address mapping table entry page.

Optionally, the update time variable value of the address mapping table entry page in the cache is updated in the following manner:

when detecting that an address mapping table entry page in a cache is updated, updating the value of an update time variable corresponding to the address mapping table entry page;

and when the address mapping table entry page is issued to the hard disk, restoring the variable value of the updating times corresponding to the address mapping table entry page to the initial value.

Optionally, the method further includes:

when a shutdown instruction is received, a specified address mapping table entry page in the current cache is issued to the hard disk;

and executing shutdown operation after the issuing is completed.

Optionally, a first sub-mapping table is pre-created in the address mapping table entry page in the cache; the first sub-mapping table is used for recording the updated address mapping table entry in the address mapping table entry page;

the method further comprises the following steps:

and when a power-off interrupt signal is received, issuing a first sub-mapping table corresponding to a specified address mapping table entry page in the current cache to the hard disk.

Optionally, the reading at least one address mapping table entry page in the hard disk of the device to the cache of the device for recording includes:

after the device is started, reading all address mapping table item pages and a first sub mapping table stored in a hard disk of the device, if the first sub mapping table can be read, updating the address mapping table item pages corresponding to the read first sub mapping table by using the read first sub mapping table, and recording all current address mapping table item pages in a cache of the device after the updating is finished;

and if the first sub mapping table cannot be read, reading all address mapping table entry pages in the hard disk of the equipment to the cache of the equipment for recording.

Optionally, after determining the designated address mapping table entry page to be issued meeting the issue condition according to the update times of each designated address mapping table entry page and issuing the designated address mapping table entry page to the hard disk of the device, the method further includes:

and clearing the first sub-mapping table corresponding to the to-be-issued specified address mapping table entry page.

According to a second aspect of the present application, there is provided an address mapping table entry page management apparatus, which is applied to a storage device, and includes:

the recording unit is used for reading all address mapping table entry pages in the hard disk of the equipment into the cache of the equipment for recording after the equipment is started;

the updating unit is used for updating an address mapping table entry page corresponding to the updated data in the cache when the data stored in the equipment is updated;

a determining unit, configured to determine, in all address mapping table entry pages recorded in the cache, at least one updated specified address mapping table entry page and the number of updates corresponding to each specified address mapping table entry page;

and the issuing unit is used for determining the designated address mapping table item pages to be issued meeting the issuing conditions according to the updating times of the designated address mapping table item pages and issuing the designated address mapping table item pages to the hard disk of the equipment so as to update the address mapping table item pages stored in the hard disk.

Optionally, the issuing unit is specifically configured to issue, as the to-be-issued specified address mapping table entry page, the specified address mapping table entry page whose update time is greater than the preset update time threshold to the hard disk of the device; or when the total number of all the designated address mapping table entry pages is determined to be larger than the first number threshold, the first N designated address mapping table entry pages with the largest updating times are taken as the designated address mapping table entry pages to be issued and issued to the hard disk of the equipment, so that the total number of the designated address mapping table entry pages in the issued cache is smaller than the second number threshold; wherein the second quantity threshold is less than the first quantity threshold; n is an integer greater than zero.

Optionally, the determining unit is specifically configured to search update time variables respectively corresponding to all the address mapping table entry pages; determining the address mapping table entry page with the updating time variable value larger than the initial value as the specified address mapping table entry page; and determining the updating times of the specified address mapping table entry page according to the variable value of the corresponding updating times of the specified address mapping table entry page.

Optionally, the update time variable value of the address mapping table entry page in the cache is updated in the following manner: when detecting that an address mapping table entry page in a cache is updated, updating the value of an update time variable corresponding to the address mapping table entry page; and when the address mapping table entry page is issued to the hard disk, restoring the variable value of the updating times corresponding to the address mapping table entry page to the initial value.

Optionally, the issuing unit is further configured to issue, when a shutdown instruction is received, a specified address mapping table entry page in the current cache to the hard disk; and executing shutdown operation after the issuing is completed.

and the issuing unit is further configured to issue the first sub-mapping table corresponding to the address mapping table entry page specified in the current cache to the hard disk when the power-off interrupt signal is received.

Optionally, the recording unit is specifically configured to, after the device is started, read all address mapping table entry pages and a first sub mapping table stored in a hard disk of the device, if the first sub mapping table can be read, update an address mapping table entry page corresponding to the read first sub mapping table by using the read first sub mapping table, and record all current address mapping table entry pages in a cache of the device after the update is completed; and if the first sub mapping table cannot be read, reading all address mapping table entry pages in the hard disk of the equipment to the cache of the equipment for recording.

Optionally, the apparatus further comprises:

and the clearing unit is used for clearing the first sub-mapping table corresponding to the to-be-issued specified address mapping table entry page.

Compared with the prior art that the address mapping table entry page is updated every time the address mapping table entry page is detected, the hard disk stores the updated address mapping table entry page in a new space, the address mapping table entry page is updated in the cache firstly, when the updating times of the updated address mapping table entry page meet the issuing condition, in other words, when the difference between the updated address mapping table entry page and the original address mapping table entry page meets a certain requirement, the updated address mapping table entry page is issued to the hard disk, and therefore the management method can save the space for the hard disk to store the updated address mapping table entry page.

Drawings

FIG. 1 is a diagram illustrating an address map table entry page and a first sub-map table according to an exemplary embodiment of the present application;

FIG. 2 is a flowchart illustrating a method for managing address map entry pages according to an exemplary embodiment of the present application;

FIG. 3 is a hardware block diagram of a memory device according to an exemplary embodiment of the present application;

fig. 4 is a block diagram illustrating an address map table entry page management apparatus according to an exemplary embodiment of the present application.

Detailed Description

Reference will now be made in detail to the exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, like numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present application, as detailed in the appended claims.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used in this application 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 also be understood that the term "and/or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.

It is to be understood that although the terms first, second, third, etc. may be used herein to describe various information, such information should not be limited to these terms. These terms are only used to distinguish one type of information from another. For example, first information may also be referred to as second information, and similarly, second information may also be referred to as first information, without departing from the scope of the present application. The word "if" as used herein may be interpreted as "at … …" or "when … …" or "in response to a determination", depending on the context.

The storage device described in this application may be a Solid State Disk (SSD), or may be other types of storage devices, and the storage device is only exemplarily described herein, and is not specifically limited to the storage device. It should be noted that the solid state disk also has a CPU, a storage medium, a communication interface, and the like, and although the name of the solid state disk has a "hard disk," the solid state disk is actually a storage device.

Before introducing the management method for address mapping table entry pages provided by the present application, some concepts related to the present application will be introduced.

1) Address mapping table entry page

The storage device may store hundreds of thousands or even millions of address mapping table entries, and in order to facilitate management of the address mapping table entries, a certain number of address mapping table entries are generally managed in a certain unit, and the unit for managing the certain number is referred to as an address mapping table entry page. The address mapping table entry page comprises a plurality of address mapping table entries, and each address mapping table entry is used for recording a logical address and a physical address mapping relation of data corresponding to the address mapping table entry.

Taking the storage device as a solid state disk as an example, a description is given to an address mapping table entry page in the solid state disk. The page of the address mapping table entry in the solid state disk is shown in table 1.

Address mapping table entry sequence number	Logical addresses	Physical address
			Table item 1	1	A chan B die C block p1 s1
Table entry 2	2	D chan E die F block p1 s1
			…	…	…
Table entry N	N	X chan X die X block p1 s4

TABLE 1

It should be noted that a Sector of the solid state disk is the smallest storage unit of the solid state disk, multiple sectors may form one Page, multiple pages may form one Block (physical Block), multiple blocks form one Plane (Plane unit), and multiple planes form one Die (core unit). The solid state disk usually includes a plurality of memory chips, each memory chip is composed of a plurality of Die, and a channel connecting each memory chip is called chan, in other words, chan is equivalent to identification information of the memory chip.

The table entry 1 in table 1 is used as an example for brief description. The logical address "1" represents a logical address identification, such as a number of a logical unit, and the like. The physical address "a chan B die C block p1s 1" indicates that data is actually stored in the first area of the first page on the physical block C in the core unit B in the memory chip connected to the channel a.

Table 1 is merely an exemplary illustration of an address map entry page, and the address map entry page is not specifically limited.

2) The first sub mapping table:

in this embodiment of the present application, when the SSD reads all address mapping table entry pages in the local hard disk to the cache of the device for the first time, the SSD may create a first sub-mapping table for each address mapping table entry page in the cache, where the first sub-mapping table is used to record an updated address mapping table entry in the address mapping table entry page corresponding to the first sub-mapping table.

As shown in fig. 1, it is assumed that there are 3 address map table entry pages, which are address map table entry page 1, address map table entry page 2, and address map table entry page 3. The application configures a first sub-mapping table for the 3 address mapping table entry pages respectively.

The address mapping table entry page 1 corresponds to the first sub-mapping table 1, the address mapping table entry page 2 corresponds to the first sub-mapping table 2, and the address mapping table entry page 3 corresponds to the first sub-mapping table 3.

As shown in fig. 1, the address map entries in gray in fig. 1 are updated address map entries, and the address map entries in white are not updated address map entries.

Taking address mapping table entry page 1 as an example, in fig. 1, if table entry 4, table entry 7, table entry 10,. and table entry 998 in address mapping table entry page 1 are updated, then updated table entry 4, table entry 7, table entry 10, …, and table entry 998 are recorded in the first sub mapping table corresponding to address mapping table entry page 1.

The contents recorded in the first sub-mapping table 2 and the first sub-mapping table 3 are shown in fig. 1, and are not described herein again.

First, the management method of the address mapping table entry page provided by the present application is briefly introduced.

After the storage device is started, the storage device can read all address mapping table entry pages in the hard disk of the storage device into the cache of the storage device for recording.

In the operation process of the storage device, when the data stored in the storage device is updated, the storage device can update the address mapping table entry page corresponding to the updated data.

After the address mapping table entry page in the cache is updated, the address mapping table entry page is not immediately issued to the hard disk, but the address mapping table entry page in the cache is waited to meet an issuing condition, in other words, when the difference between the address mapping table entry page after being updated in the cache and the original address mapping table entry page meets a certain requirement, the address mapping table entry page with the difference meeting the certain requirement is issued to the hard disk so as to update the address mapping table entry page stored in the hard disk.

Compared with the prior art that the address mapping table entry page is updated every time the address mapping table entry page is detected, the hard disk uses a new physical space to store the updated address mapping table entry page, the method for updating the address mapping table entry page of the hard disk is implemented by updating the address mapping table entry page in the cache firstly and issuing the address mapping table entry page in the cache to the hard disk only when the difference between the address mapping table entry page before and after the update meets a certain requirement, and the method greatly reduces the space loss of the hard disk caused by updating the address mapping table entry page.

In addition, when an access request is received, the stored data can search an address mapping table corresponding to the logical address of the data to be accessed carried by the access request in the cache, and then read the data according to the physical address recorded in the searched address mapping table, instead of reading the address mapping table corresponding to the access request from the hard disk in the prior art, because the speed of reading the address mapping table from the cache is far higher than the speed of reading the address mapping table from the hard disk, the efficiency of reading the data is greatly improved.

In addition, a first sub-mapping table is created for each address mapping table item page in the cache, the first sub-mapping table is used for recording the address mapping table items after the address mapping table item page corresponding to the first sub-mapping table is updated, and when the device is abnormally powered off, the first sub-mapping table corresponding to each updated address mapping table item page can be issued to the hard disk. The updated address mapping table entry page is not issued to the hard disk, but the updated address mapping table entry (namely, the first sub-mapping table) of the specified address mapping table entry page is issued to the hard disk, so that the data volume required to be issued after abnormal power failure is greatly reduced, and the quantity of capacitors supporting the data volume issue is also greatly reduced due to the fact that the data volume required to be issued is greatly reduced, so that the cost of the storage device can be reduced.

The following describes the management method of the address mapping table entry page provided by the present application in detail.

Referring to fig. 2, fig. 2 is a flowchart illustrating an address map table entry page management method according to an exemplary embodiment of the present application, where the flowchart may be applied to a storage device, and may include the following steps.

Step 201: after the device is started, the storage device can read all address mapping table entry pages in the hard disk of the device to the cache of the device for recording.

After the storage device is abnormally powered off (for example, the storage device is suddenly powered off), the storage device can utilize the capacitor of the storage device to send the data stored in the cache to the hard disk. The more the capacitance of the storage device is, the higher the cost of the storage device is.

In order to reduce the cost of the storage device, the first sub-mapping table is created for each address mapping table entry page in the cache, and the first sub-mapping table is used for recording the updated address mapping table entry in the address mapping table entry page corresponding to the first sub-mapping table.

When the storage device is abnormally powered off, the related hardware of the storage device can generate a power-off interrupt signal, and after the CPU of the storage device receives the power-off interrupt signal, the CPU can issue the first sub-mapping tables corresponding to all address mapping table entry pages in the current cache to the hard disk of the storage device. Because the designated address mapping table entry page is not issued to the hard disk, but the address mapping table entry (namely, the first sub-mapping table) updated by the designated address mapping table entry page is issued to the hard disk, the data volume to be issued after abnormal power failure is greatly reduced, and because the data volume to be issued is greatly reduced, the number of capacitors supporting the data volume to be issued is also greatly reduced, so that the cost of the storage device can be reduced.

Therefore, after the device is started, if the first sub-mapping table is stored in the hard disk, the first sub-mapping table and all address mapping table entry pages in the hard disk need to be read, the address mapping table entry pages are updated by using the first sub-mapping table, and the address mapping table entry pages are written into the cache after the update is completed, so that the address mapping table entry pages can be restored to the last abnormal power failure state, and if the first sub-mapping table is not stored in the hard disk, all address mapping table entry pages in the hard disk can be directly read for recording.

In specific implementation, after the device is started, the storage device may read all address mapping table entry pages and the first sub-mapping table stored in the hard disk of the device, if the first sub-mapping table can be read, update the address mapping table entry page corresponding to the first sub-mapping table by using the first sub-mapping table, and record all current address mapping table entry pages (including the updated address mapping table entry page and the non-updated address mapping table entry page) in the cache of the device after the update is completed.

For example, the number of all address mapping table entry pages read by the storage device is 10, which are respectively the address mapping table entry page 1 to the address mapping table entry page 10, and the number of the first sub-mapping tables is 2, which are respectively the first sub-mapping table 5 and the first sub-mapping table 10. The first sub-mapping table 5 corresponds to the address mapping table entry page 5, and the first sub-mapping table 10 corresponds to the address mapping table entry page 10.

The storage device may update the address map entry page 5 using the first sub-map table 5, update the address map entry page 10 using the first sub-map table 10, and then record the updated address map entry page 5, the address map entry page 10, and the un-updated address map entry pages 1 to 4, and the address map entry pages 6 to 9 in the cache.

And if the storage equipment cannot read the first sub mapping table, directly recording all read address mapping table entry pages in the cache.

Step 202: when the data stored in the storage device is updated, the address mapping table entry page corresponding to the updated data in the cache is updated.

During the operation of the storage device, when new data is written or stored data needs to be modified, the update of the address mapping table entry page can occur.

In implementation, when new data is written, the storage device may add a mapping relationship between a logical address and a physical address of the new written data in any address mapping table entry page in the cache.

When there is stored data to be modified, the storage device may write the modified data into a new physical space, then use the logical address of the data to be modified as a key, search an address mapping table entry corresponding to the key in an address mapping table entry page in the cache, and then modify the physical address in the address mapping table entry into an address newly written into the physical space.

For example, assuming that the logical address of the data to be modified is M, the physical address of the storage device writing the modified data into the new physical space is a. The storage device uses M as a key word, and searches an address mapping table item containing M in an address mapping table item page in the cache. Assuming that the found address mapping table entry is M-B, wherein the logical address is M, and the physical address is B, the physical address in the address mapping table entry is modified from B to a, that is, the address mapping table entry in the address mapping table entry page is modified to M-a.

Step 203: the storage device may determine, among all address mapping table entry pages recorded in the cache, at least one specified address mapping table entry page that is updated and the number of updates corresponding to each specified address mapping table entry page.

It should be noted that the triggering condition for executing step 203 to step 204 is not specifically limited, for example, the present apparatus may execute step 203 to step 204 when detecting that the address mapping table entry page in the cache is updated; alternatively, the present apparatus may also periodically perform step 203 to step 204.

It should be further noted that, the updating of the address mapping table entry page described herein means that the address mapping table entry in the address mapping table entry page is updated, and the address mapping table entry page is also updated. For example, if an address mapping table entry is added to the address mapping table entry page, the address mapping table entry page is updated, and if an address mapping table entry in the address mapping table entry page is modified, the address mapping table entry page is updated.

When the method is realized, the updating time variable is set for each address mapping table item page, and the initial value of the updating time variable of each address mapping table item page is the same. The update times variable is used for counting the update times of each address mapping table entry page.

When the storage device detects that the address mapping table entry page in the cache is updated, the storage device may update the update time variable corresponding to the updated address mapping table entry page.

The initial value of the update time variable and the mode of updating the update time variable are not specifically limited in the present application. For example, the initial value of the update time variable may be 0, and each time an address mapping table entry page is updated, the update time variable corresponding to the address mapping table entry page is incremented by 1. Of course, the initial value of the update time variable may also be an integer greater than 0, and each time the address mapping table entry page is updated, the update time variable corresponding to the address mapping table entry page is increased by a preset value. The examples are illustrative only and not intended to be limiting.

In addition, in this embodiment of the present application, after the storage device detects that an address mapping table entry page is issued to the hard disk in the cache, the update time variable corresponding to the issued address mapping table entry page is restored to the initial value.

It should be noted that the address mapping table entry page is issued to the hard disk, the address mapping table entry page is not deleted in the cache, and the update time variable of the address mapping table entry page issued to the hard disk is restored to the initial value, so as to make the address mapping table entry page in the cache serve as the non-updated address mapping table entry page again, perform the update statistics again, and issue the address mapping table entry page to the hard disk when the condition is met next time.

In this embodiment of the present application, when determining the updated specified address mapping table entry page and the update times of the specified address mapping table entry page, the storage device may first search for an update time variable corresponding to each address mapping table entry page, and then determine, as the specified address mapping table entry page, an address mapping table entry page whose update time variable is greater than an initial value.

Then, the storage device may determine the update times of the specified address mapping table entry page according to the value of the update times variable corresponding to the specified address mapping table entry page.

It should be noted that, according to the value of the update time variable corresponding to the specified address mapping table entry page, it is determined that the update time of the specified address mapping table entry page is related to the update mode of the update time variable.

For example, if the initial value of the update time variable is 0, and each time the address mapping table entry page is updated, the value of the update time variable corresponding to the address mapping table entry page is incremented by 1, the storage device may determine the address mapping table entry page whose value of the update time variable is greater than 0 as the specified address mapping table entry page, and when the update time of the specified address mapping table entry page is determined according to the value of the update time variable corresponding to the specified address mapping table entry page, the storage device may directly use the value of the update time variable of the specified address mapping table entry page as the update time of the specified address mapping table entry page.

For another example, assuming that the initial value of the update time variable is M, and the value of the update time variable corresponding to the address mapping table entry page is added with P every time the address mapping table entry page is updated, the storage device may determine the address mapping table entry page whose value of the update time variable is greater than M as the specified address mapping table entry page, and when the update time of the specified address mapping table entry page is determined according to the value of the update time variable corresponding to the specified address mapping table entry page, the storage device may subtract M from the value of the update time variable of the specified address mapping table entry page and then divide the value by P to obtain the update time of the specified address mapping table entry page. Wherein M and P are both integers greater than 0. The examples are illustrative only and not intended to be limiting.

Of course, the storage device may also mark an update flag for the updated address mapping table entry page when detecting that the address mapping table entry page is updated once, the storage device may determine the address mapping table entry page carrying the update flag as the specified address mapping table entry page, and determine the total number of the update flags on the specified address mapping table entry page as the number of updates of the specified address mapping. The determination of the specified address map entry page and the number of updates to the specified address map entry page is merely exemplary and not particularly limited.

Step 204: the storage device can determine the designated address mapping table item pages to be issued meeting the issuing condition according to the updating times of the designated address mapping table item pages and issues the designated address mapping table item pages to the hard disk of the storage device so as to update the address mapping table item pages stored in the hard disk.

The first method is as follows:

the storage device can take the designated address mapping table entry page with the updating times larger than the preset updating time threshold as the designated address mapping table entry page to be issued and issue the designated address mapping table entry page to the hard disk of the storage device.

For example, if the preset update time threshold is 800 times, the address mapping table entry page with the update time greater than 800 times is used as the specified address mapping table entry page to be issued, and is issued to the hard disk of the device.

The second method comprises the following steps:

first, the storage device may count the total number of all specified address map entry pages.

Then, the storage device may detect whether the total number of all designated address mapping table entry pages is greater than a first number threshold, and if the total number of all designated address mapping table entry pages is greater than the first number threshold, the storage device may sort the designated address mapping table entry pages in order of decreasing update times.

And the storage equipment sequentially issues the first N designated address mapping table item pages to the hard disk of the storage equipment according to the sequence from the first designated address mapping table item page in the sequence until the total number of the currently updated designated address mapping table item pages is less than the second number threshold.

For example, the first number threshold is 30, the second number threshold is 10, and it is assumed that the number of the updated specified address mapping table entry pages is 32.

The storage device may sort the 32 address mapping table entry pages in the descending order of the update times, then issue the first address mapping table entry page in the order to the hard disk, and after the issuance is completed, detect whether the total number of the designated mapping tables in the current cache is less than a second number threshold (i.e. 10).

In this example, if the total number (i.e. 31) of the designated mapping tables in the current cache is greater than the second number threshold (i.e. 10), then the second ordered address mapping table entry page is issued, and so on, until after the address mapping table entry page ordered at 23 is issued, the total number (i.e. 9) of the designated address mapping table entry pages in the current cache is less than the second number threshold (i.e. 10).

The second number threshold is set to be not 0 or set to be very small, which aims to prevent the address mapping table entry page with the smaller updating times from being written into the hard disk. And the first number threshold should not be set too large or too small. If the first number threshold is set to be too large, a large number of address mapping table entry pages need to be written into the hard disk when the storage device receives a shutdown instruction, and shutdown time is greatly increased. If the first number threshold is set too small, frequent writes to pages of the address mapping table entry may result.

It should be noted that, because the solid state disk does not support the overwriting operation, the specified address mapping table entry page to be issued that meets the condition is issued to the hard disk to update the address mapping table entry page in the hard disk, instead of covering the originally stored address mapping table entry page in the hard disk with the issued specified address mapping table entry page, the issued address mapping table entry page is written into a new physical storage space.

It should be noted that, no matter in the first mode or the second mode, the present application does not issue all the specified address mapping table pages to the hard disk, but only issues the specified address mapping table pages meeting the conditions to the hard disk to update the address mapping table pages in the hard disk when the update times of the specified address mapping table pages meet the issue conditions, so that the present application does not detect the update of the address mapping table pages, and issues the updated address mapping table pages, but the updated address mapping table pages have more update times, in other words, when the difference between the updated address mapping table pages and the address mapping table pages before update is large, the updated address mapping table pages are issued to the hard disk at one time.

Therefore, compared with the prior art that the hard disk uses a new space to store the updated address mapping table page every time the address mapping table page is detected to be updated, the method updates the address mapping table page in the cache, and issues the updated address mapping table page to the hard disk only when the difference between the updated address mapping table page and the original address mapping table page meets a certain requirement, so that the space for storing the updated address mapping table page by the hard disk can be saved by using the management method.

For example, the address mapping table entry page is updated 5 times, and in the existing method, the hard disk requests 5 new spaces to store the address mapping table entry page after each update. The address mapping table entry page is updated once in the cache, if the issuing condition is not met, the previous steps are circulated, the address mapping table entry page in the cache is updated, if the issuing condition is met after 5 times of updating, the address mapping table entry page updated for 5 times in the cache is issued to the hard disk, namely, the new space of the hard disk application 1 stores the address mapping table entry page updated for 5 times, and therefore internal space resource consumption in the hard disk storage process is greatly reduced.

In this embodiment of the present application, after determining, according to the number of updates of each specified address mapping table entry page, a specified address mapping table entry page to be issued that meets an issue condition and issues to a hard disk of the device, the storage device may empty a first sub-mapping table corresponding to the specified address mapping table entry page to be issued.

The method comprises the steps of sending an address mapping table item page, copying the address mapping table item page and sending the address mapping table item page to a hard disk, and not deleting the address mapping table item page in a cache, so that a first sub-mapping table corresponding to the sent address mapping table item page is emptied, and the purpose is to enable the sent address mapping table item page to be used as an un-updated address mapping table item page again in the cache to carry out the updating and sending operation.

In addition, in this embodiment of the present application, when the storage device receives a shutdown instruction, the storage device may issue the updated specified address mapping table entry page in the current cache to the hard disk, and after the issuance is completed, perform a shutdown operation.

As can be seen from the above description, on one hand, compared with the existing method that each time an address mapping table entry page is detected to be updated, the hard disk uses a new space to store the updated address mapping table entry page, the address mapping table entry page is updated in the cache in the present application, and when the update times of the updated address mapping table entry page satisfy the issue condition, in other words, when the difference between the updated address mapping table entry page and the original address mapping table entry page satisfies a certain requirement, the updated address mapping table entry page is issued to the hard disk, so that the space for the hard disk to store the updated address mapping table entry page can be saved by using the management method of the present application.

On the other hand, the address mapping table entry page is preconfigured with a first sub-mapping table, and the first sub-mapping table is used for recording the updated address mapping table entries in the address mapping table entry pages. And after receiving a power-off interrupt signal, issuing the first sub-mapping table of the specified address mapping table entry page in the cache to the hard disk.

Because the designated address mapping table entry page is not issued to the hard disk, but the address mapping table entry (namely, the first sub-mapping table) updated by the designated address mapping table entry page is issued to the hard disk, the data volume to be issued after abnormal power failure is greatly reduced, and because the data volume to be issued is greatly reduced, the number of capacitors supporting the data volume to be issued is also greatly reduced, so that the cost of the storage device can be reduced.

In the third aspect, because the issued address mapping table entry page is greatly different from the original mapping table entry page, the same data of the issued address mapping table entry page and the original address mapping table entry page stored in the new storage space of the hard disk is less, so that the write amplification (i.e. the same data is repeatedly written into the hard disk) can be effectively reduced, and the storage space of the hard disk is effectively saved.

In a fourth aspect, after the storage device is locally started, all address mapping table entry pages in the hard disk of the storage device are read into the cache of the storage device for recording, so that when the storage device receives an access request, the address mapping table entry corresponding to the access request can be directly read from the cache, and then the data in the hard disk is read through the read address mapping table entry, instead of the existing address mapping table entry corresponding to the access request being read from the hard disk, because the speed of reading the address mapping table entry from the cache is far greater than the speed of reading the address mapping table entry from the hard disk, the efficiency of reading the data is greatly improved.

The following describes in detail the address mapping table entry page management method provided by the present application, with the above storage device being an SSD and in combination with two specific embodiments.

Example 1:

and after the SSD is started, reading an address mapping table entry page and a first sub mapping table stored in the hard disk. If the first sub-mapping table can be read, updating the address mapping table entry page corresponding to the first sub-mapping table by using the read first sub-mapping table, and writing the updated address mapping table entry page and the non-updated address mapping table entry page into the cache of the device for recording.

And if the first sub mapping table cannot be read, directly writing the read address mapping table entry page into the cache for recording.

In addition, after the SSD is started, the SSD may initialize the update time variable corresponding to each address mapping table entry page and the first sub mapping table corresponding to each address mapping table entry page.

In the running process of the SSD, if the fact that the locally stored data is updated is detected, an address mapping table item page corresponding to the updated data in the cache is updated, the value of an update time variable of the address mapping table item page is updated, and the updated address mapping table item is written into a first sub mapping table corresponding to the address mapping table item page.

The SSD may count the total number of the designated address mapping table entry pages whose values of the current update time variable are greater than the initial value when it is detected that the address mapping table entry page is updated in the cache, or periodically, and determine the update time of the designated address mapping table entry page according to the update time variable value corresponding to the designated address mapping table entry page.

Then, the SSD may detect whether the counted total number of the designated address mapping table entry pages is greater than a first number threshold, and if the counted total number of the designated address mapping table entry pages is greater than the first number threshold, sort the designated address mapping table entry pages in descending order of the update times, and issue the top N designated address mapping table entry pages that are sorted in the front to the hard disk, so that the total number of the designated address mapping table entry pages in the current cache is less than a second number threshold. Then, the SSD may restore the values of the variable of the update times of the first N designated address mapping table entry pages to the initial values, and empty the first sub-mapping tables of the first N designated address mapping table entry pages at the same time.

And when the SSD receives a shutdown instruction, the SSD can issue the specified address mapping table entry page in the current cache to the hard disk. And after the distribution is finished, executing shutdown operation.

When the SSD receives a power-off interrupt signal, the SSD can issue a first sub-mapping table corresponding to a specified address mapping table entry page in the current cache to the hard disk.

Example 2:

The SSD can determine the updating times of each address mapping table item page according to the values of the updating time variables of each address mapping table item page periodically or when detecting that the address mapping table item page is updated in the cache, issue the address mapping table item page with the updating times larger than the preset updating time threshold value into the cache, restore the values of the updating time variables corresponding to the address mapping table item page issued into the cache to initial values, and clear the first sub-mapping table of the issued address mapping table item page.

Referring to fig. 3, fig. 3 is a hardware structure diagram of a storage device according to an exemplary embodiment of the present application.

The storage device includes: a communication interface 301, a processor 302, a machine-readable storage medium 303, and a bus 304; wherein the communication interface 301, the processor 302, and the machine-readable storage medium 303 communicate with each other via a bus 304. The processor 302 may perform the address map entry page management method described above by reading and executing machine-executable instructions in the machine-readable storage medium 303 corresponding to the address map entry page management control logic.

The machine-readable storage medium 303 referred to herein may be any electronic, magnetic, optical, or other physical storage device that can contain or store information such as executable instructions, data, and the like. For example, the machine-readable storage medium may be: volatile memory, non-volatile memory, or similar storage media. In particular, the machine-readable storage medium 303 may be a RAM (random Access Memory), a flash Memory, a storage drive (e.g., a hard drive), a solid state drive, any type of storage disk (e.g., a compact disk, a DVD, etc.), or similar storage medium, or a combination thereof.

Referring to fig. 4, fig. 4 is a block diagram illustrating an address map table entry page management apparatus according to an exemplary embodiment of the present application. The apparatus is applicable to a storage device and may include the following elements.

The recording unit 401 is configured to read all address mapping table entry pages in the hard disk of the device into the cache of the device for recording after the device is started;

an updating unit 402, configured to update, when data stored in the local device is updated, an address mapping table entry page corresponding to the updated data in the cache;

a determining unit 403, configured to determine, in all address mapping table entry pages recorded in the cache, at least one updated specified address mapping table entry page and the number of updates corresponding to each specified address mapping table entry page;

the issuing unit 404 is configured to determine, according to the update times of each specified address mapping table entry page, a specified address mapping table entry page to be issued that meets the issuing condition, and issue the specified address mapping table entry page to the hard disk of the device, so as to update the address mapping table entry page stored in the hard disk.

Optionally, the issuing unit 404 is specifically configured to issue, as a to-be-issued specified address mapping table entry page, the specified address mapping table entry page whose update time is greater than the preset update time threshold to the hard disk of the device; or when the total number of all the designated address mapping table entry pages is determined to be larger than the first number threshold, the first N designated address mapping table entry pages with the largest updating times are taken as the designated address mapping table entry pages to be issued and issued to the hard disk of the equipment, so that the total number of the designated address mapping table entry pages in the issued cache is smaller than the second number threshold; wherein the second quantity threshold is less than the first quantity threshold; n is an integer greater than zero.

Optionally, the determining unit 403 is specifically configured to search update time variables respectively corresponding to all the address mapping table entry pages; determining the address mapping table entry page with the updating time variable value larger than the initial value as the specified address mapping table entry page; and determining the updating times of the specified address mapping table entry page according to the variable value of the corresponding updating times of the specified address mapping table entry page.

Optionally, the issuing unit 404 is further configured to issue, when a shutdown instruction is received, a specified address mapping table entry page in the current cache to the hard disk; and executing shutdown operation after the issuing is completed.

the issuing unit 404 is further configured to issue, when a power-off interrupt signal is received, the first sub-mapping table corresponding to the address mapping table entry page specified in the current cache to the hard disk.

Optionally, the recording unit 401 is specifically configured to, after the device is started, read all address mapping table entry pages and a first sub mapping table stored in a hard disk of the device, if the first sub mapping table can be read, update an address mapping table entry page corresponding to the read first sub mapping table by using the read first sub mapping table, and record all current address mapping table entry pages in a cache of the device after the update is completed; and if the first sub mapping table cannot be read, reading all address mapping table entry pages in the hard disk of the equipment to the cache of the equipment for recording.

Optionally, the apparatus further comprises:

and an emptying unit 405, configured to empty the first sub-mapping table corresponding to the to-be-issued specified address mapping table entry page.

The implementation process of the functions and actions of each unit in the above device is specifically described in the implementation process of the corresponding step in the above method, and is not described herein again.

For the device embodiments, since they substantially correspond to the method embodiments, reference may be made to the partial description of the method embodiments for relevant points. The above-described embodiments of the apparatus are merely illustrative, and the units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the scheme of the application. One of ordinary skill in the art can understand and implement it without inventive effort.

The above description is only exemplary of the present application and should not be taken as limiting the present application, as any modification, equivalent replacement, or improvement made within the spirit and principle of the present application should be included in the scope of protection of the present application.

Claims

1. An address mapping table entry page management method, applied to a storage device, includes:

determining the designated address mapping table entry pages to be issued which meet the issuing condition according to the updating times of the designated address mapping table entry pages, and issuing the designated address mapping table entry pages to the hard disk of the equipment so as to update the address mapping table entry pages stored in the hard disk;

a first sub mapping table is pre-created in an address mapping table entry page in the cache; the first sub-mapping table is used for recording the updated address mapping table entry in the address mapping table entry page;

the method further comprises the following steps:

2. The method according to claim 1, wherein the determining the pages of the to-be-issued specified address mapping table entries meeting the issuing condition according to the update times of each specified address mapping and issuing the pages to the hard disk of the device comprises:

alternatively, the first and second electrodes may be,

3. The method of claim 1, wherein determining the at least one specified address map entry page that has been updated and the number of updates associated with each specified address map entry page comprises:

4. The method of claim 3, wherein the variable value of the update times of the address mapping table entry page in the cache is updated as follows:

5. The method of claim 1, further comprising:

and executing shutdown operation after the issuing is completed.

6. The method according to claim 1, wherein reading at least one address mapping table entry page in a hard disk of the present device into a cache of the present device for recording comprises:

7. The method according to claim 1, wherein after determining the designated address mapping table entry page to be delivered that meets the delivery condition according to the number of updates of each designated address mapping table entry page and delivering the designated address mapping table entry page to the hard disk of the device, the method further comprises:

8. An address mapping table entry page management apparatus, applied to a storage device, includes:

the issuing unit is used for determining the designated address mapping table item pages to be issued meeting the issuing conditions according to the updating times of the designated address mapping table item pages and issuing the designated address mapping table item pages to the hard disk of the equipment so as to update the address mapping table item pages stored in the hard disk;

9. The apparatus according to claim 8, wherein the issuing unit is specifically configured to issue, as the designated address mapping table entry page to be issued, the designated address mapping table entry page whose update time is greater than a preset update time threshold to a hard disk of the device; or when the total number of all the designated address mapping table entry pages is determined to be larger than the first number threshold, the first N designated address mapping table entry pages with the largest updating times are taken as the designated address mapping table entry pages to be issued and issued to the hard disk of the equipment, so that the total number of the designated address mapping table entry pages in the issued cache is smaller than the second number threshold; wherein the second quantity threshold is less than the first quantity threshold; n is an integer greater than zero.

10. The apparatus according to claim 8, wherein the determining unit is specifically configured to search update time variables respectively corresponding to all the address mapping table entry pages; determining the address mapping table entry page with the updating time variable value larger than the initial value as the specified address mapping table entry page; and determining the updating times of the specified address mapping table entry page according to the variable value of the corresponding updating times of the specified address mapping table entry page.

11. The apparatus of claim 10, wherein the variable value of the update times of the address mapping table entry page in the cache is updated as follows: when detecting that an address mapping table entry page in a cache is updated, updating the value of an update time variable corresponding to the address mapping table entry page; and when the address mapping table entry page is issued to the hard disk, restoring the variable value of the updating times corresponding to the address mapping table entry page to the initial value.

12. The apparatus according to claim 8, wherein the issuing unit is further configured to issue, when a shutdown instruction is received, a specified address mapping table entry page in a current cache to the hard disk; and executing shutdown operation after the issuing is completed.

13. The apparatus according to claim 8, wherein the recording unit is specifically configured to, after the apparatus is started, read all address mapping table entry pages and a first sub-mapping table stored in a hard disk of the apparatus, if the first sub-mapping table can be read, update an address mapping table entry page corresponding to the read first sub-mapping table by using the read first sub-mapping table, and record all current address mapping table entry pages in a cache of the apparatus after the update is completed; and if the first sub mapping table cannot be read, reading all address mapping table entry pages in the hard disk of the equipment to the cache of the equipment for recording.

14. The apparatus of claim 8, further comprising: