CN111949201A - A storage device and its control method and control device - Google Patents

Abstract

Embodiments of the present invention disclose a storage device and a control method and control device thereof. The storage device includes a storage module, and the storage module includes a plurality of physical blocks. The control method includes: if it is detected that the erasing times of the physical blocks are greater than or equal to The first erasing threshold is switched to the wear leveling mode; the data of the first physical block and the data of the second physical block are moved and exchanged, the erasing times of the first physical block is less than the first erasing threshold, and the second physical block is The number of times of erasing is greater than the first erasing threshold. In the embodiment of the present invention, the data of the first physical block and the second physical block are exchanged, and the frequently updated data is moved to the first physical block, so that the erasing opportunities of the first physical block are increased, while the erasing opportunities of the second physical block are increased. The removal opportunity is reduced, thereby reducing the difference in the number of erasures between at least two physical blocks, improving the wear leveling effect, achieving a balanced use of physical blocks, reducing the degree of physical block wear, and extending the use of physical blocks on the device side. life.

Description

A storage device and its control method and control device

technical field

Embodiments of the present invention relate to storage technologies, and in particular, to a storage device and a control method and control device thereof.

Background technique

Wear leveling is one of the flash translation layer FTL algorithms that most solid-state drive SSD products will implement. Its core idea is to balance the erasing and writing times of all physical blocks on the device side.

In the prior art, a randomness algorithm is used to implement a wear leveling mechanism, and specifically, a certain physical block is randomly selected for an erasing operation according to a uniform distribution probability. Regardless of whether the physical block contains "cold" data or "hot" data, let each physical block have an equal probability of being erased, and then copy the valid data in the original block to an empty block and erase the block.

Obviously, the effect of this algorithm is greatly affected by random factors, and the number of erasures of each block cannot reach equal probability, so it cannot achieve a good wear balance effect.

SUMMARY OF THE INVENTION

Embodiments of the present invention provide a storage device and a control method and control device thereof, so as to improve the wear leveling effect.

An embodiment of the present invention provides a control method for a storage device, where the storage device includes a storage module, and the storage module includes a plurality of physical blocks, and the control method includes:

If it is detected that the erasing times of the physical block is greater than or equal to the first erasing threshold, switch to the wear leveling mode;

The data of the first physical block and the data of the second physical block are moved and exchanged, wherein the erasing times of the first physical block is less than the first erasing threshold, and the erasing times of the second physical block is greater than the first erase threshold.

Further, the first erasing threshold is equal to the mean value of erasing times of a plurality of physical blocks in the storage module.

Further, moving and exchanging the data of the first physical block and the data of the second physical block includes:

Determining the physical block with the smallest number of erasures among the plurality of physical blocks as the first physical block, determining the physical block with the largest number of erasures among the plurality of physical blocks as the second physical block, and swapping data of the first physical block and the second physical block.

Further, before detecting that the erasing times of the physical block is greater than or equal to the first erasing threshold, the method further includes:

Receive the first operation command, determine the physical block corresponding to the first operation command, and then detect whether the erasing times of the physical block is greater than or equal to the first erasing threshold.

Based on the same inventive concept, an embodiment of the present invention further provides a control device for a storage device, the storage device includes a storage module, the storage module includes a plurality of physical blocks, and the control device includes:

a mode switching module, configured to switch to the wear leveling mode if it is detected that the erasing times of the physical block is greater than or equal to the first erasing threshold;

A data moving module, configured to move and exchange the data of the first physical block and the data of the second physical block, wherein the erasing times of the first physical block is less than the first erasing threshold, and the second physical block is erased. The number of times of erasing the block is greater than the first erasing threshold.

Further, the first erasing threshold is equal to the mean value of erasing times of a plurality of physical blocks in the storage module.

Further, the data moving module is specifically configured to determine the physical block with the smallest number of erasures among the multiple physical blocks as the first physical block, and determine the physical block with the largest number of erasures among the multiple physical blocks. A block is determined as the second physical block, and data of the first physical block and the second physical block are exchanged.

Further, it also includes:

The detection module is configured to receive the first operation command and determine the physical block corresponding to the first operation command, and then detect whether the erasing times of the physical block is greater than or equal to the first erasing threshold.

Based on the same inventive concept, an embodiment of the present invention further provides a storage device, the storage device includes a storage module and the above-mentioned control device, and the control device is electrically connected to the storage module.

In this embodiment of the present invention, a deterministic algorithm is used to determine whether a segment triggers wear leveling according to whether the number of erasures of physical blocks in the storage device is greater than or equal to the first erasure threshold, and after triggering the wear leveling mode, the number of erasures is less than the first erasure threshold. The first physical block with an erasing threshold and the data of the second physical block whose erasing times are greater than the first erasing threshold are exchanged. Since the second physical block has a large number of erasures, it means that the data of the second physical block is frequently updated to obtain more erasure opportunities, while the number of erasures of the first physical block is small, indicating that the data of the first physical block is rarely updated. Therefore, the erasure opportunities are rarely obtained. If the data of the first physical block and the second physical block are exchanged, the frequently updated data is moved to the first physical block, which increases the erasing opportunities of the first physical block, and vice versa. Therefore, the difference in the number of erasures of at least two physical blocks in the storage device is reduced, the wear leveling effect is improved, the balanced use of physical blocks is achieved, the degree of physical block wear is reduced, and the equipment is prolonged. End physical block lifetime.

Description of drawings

In order to illustrate the embodiments of the present invention or the technical solutions in the prior art more clearly, the following will briefly introduce the accompanying drawings used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description These are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained according to these drawings without creative efforts.

1 is a flowchart of a method for controlling a storage device provided by an embodiment of the present invention;

FIG. 2 is a schematic diagram of a control apparatus of a storage device according to an embodiment of the present invention.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present invention clearer, the following will refer to the accompanying drawings in the embodiments of the present invention, and describe the technical solutions of the present invention clearly and completely through the implementation manner. Obviously, the described embodiments are the present invention. Some examples, but not all examples. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

As shown in FIG. 1 , it is a flowchart of a method for controlling a storage device provided by an embodiment of the present invention. The storage device can be any chip or device integrated with a storage module, such as a solid-state hard disk integrated with flash memory particles. In other embodiments, the storage device can also be selected to be another device integrated with a storage module. Here, the storage device includes a storage module, the storage module includes a plurality of physical blocks, and the storage module writes data in units of physical blocks. In this embodiment, the control apparatus integrated in the storage device may execute the control method, and the control apparatus may be implemented by means of software and/or hardware.

The control method of the storage device provided by this embodiment includes:

Step 110: If it is detected that the erasing times of the physical block is greater than or equal to the first erasing threshold, switch to the wear leveling mode.

In this embodiment, for all physical blocks in the storage device, the control device stores the erasure times of each physical block, and the control device updates the erasure times of each physical block in time after each operation. The control device triggers wear leveling when detecting that the number of times of erasing the physical block is greater than or equal to the first erasing threshold.

It should be noted that the first erasing threshold is a parameter related to the number of physical block erasures, and its purpose is to balance the number of physical block erasing. Therefore, the first erasing threshold may be a preset fixed value, or may be An indeterminate value that varies with the number of physical block erases. For example, the optional first erasing threshold is equal to the average of erasing times of multiple physical blocks in the storage module, that is, the value obtained by summing the erasing times of each physical block in the storage device and then averaging the value is the first erasing threshold . Optionally, the first erasing threshold is equal to (m+n)/2, where m is the maximum erasing number of physical blocks in the storage device, and n is the minimum erasing number of physical blocks in the storage device. Optionally, the first erasing threshold is k, and k is a fixed value. The first erasing threshold may be reasonably set on the basis of ensuring that the physical blocks can be used in a balanced manner.

Optionally, before detecting that the erasing times of the physical block is greater than or equal to the first erasing threshold, the method further includes: receiving the first operation command and determining the physical block corresponding to the first operation command, and then detecting the erasing times of the physical block. Is greater than or equal to the first erase threshold. In this embodiment, the first operation command may be any operation command for the storage device, such as a read operation, a write operation, or an erase operation. The control device can determine the physical block corresponding to the command according to the first operation command, and then detect whether the erasing times of the physical block is greater than or equal to the first erasing threshold. The purpose of using the storage device receiving an operation command as a triggering condition for detecting the number of physical block erasures is to prevent the storage device from frequently performing wear leveling and occupying the user's erasing and writing time. Optionally, after the first operation command is executed, the data exchange of wear leveling is executed.

Step 120: Move and exchange the data of the first physical block and the data of the second physical block, wherein the erasing times of the first physical block is less than the first erasing threshold, and the erasing times of the second physical block is greater than the first erasing threshold. except threshold.

In this embodiment, after the wear leveling is triggered, the control device may select the first physical block and the second physical block for implementing the wear leveling mechanism from the plurality of physical blocks, and perform transfer and exchange to realize the first physical block and the second physical block. balanced use. Specifically, at least one physical block in which the number of erasures is less than the first erasure threshold is determined as the first physical block, and at least one physical block in which the number of erasures is greater than the first erasure threshold is determined as the second physical block, and then Swap data in the first physical block and the second physical block. It should be noted that, there may be multiple physical blocks in the storage device whose erasing times are less than the first erasing threshold. The block is used as the first physical block; there may be multiple physical blocks in the storage device whose erasing times are greater than the first erasing threshold, then at least one physical block can be selected as the second physical block, or the largest erasing times can be selected. The physical block is used as the second physical block, which is not specifically limited in the present invention.

Optionally, moving and exchanging the data of the first physical block and the data of the second physical block includes: determining the physical block with the smallest number of erasures among the multiple physical blocks as the first physical block, and erasing the multiple physical blocks. The physical block with the largest number of divisions is determined as the second physical block, and the data of the first physical block and the second physical block are exchanged. Therefore, the difference in the number of erasures in the physical block can be reduced, and a good wear balance effect can be achieved.

In this embodiment, a deterministic algorithm is used to determine whether the segment triggers wear leveling according to whether the number of times of erasing a physical block in the storage device is greater than or equal to the first erasure threshold. The data of the first physical block whose erasing threshold is greater than the first erasing threshold and the data of the second physical block whose number of times of erasing is greater than the first erasing threshold is exchanged. Since the second physical block has a large number of erasures, it means that the data of the second physical block is frequently updated to obtain more erasure opportunities, while the number of erasures of the first physical block is small, indicating that the data of the first physical block is rarely updated. Therefore, the erasure opportunities are rarely obtained. If the data of the first physical block and the second physical block are exchanged, the frequently updated data is moved to the first physical block, which increases the erasing opportunities of the first physical block, and vice versa. Therefore, the difference in the number of erasures of at least two physical blocks in the storage device is reduced, the wear leveling effect is improved, the balanced use of physical blocks is achieved, the degree of physical block wear is reduced, and the equipment is prolonged. End physical block lifetime.

Based on the same inventive concept, an embodiment of the present invention further provides a control apparatus for a storage device, where the control apparatus can execute the control method described in any of the foregoing embodiments. The storage device includes a storage module, and the storage module includes a plurality of physical blocks.

The control apparatus of the storage device provided in this embodiment includes: a mode switching module 210, configured to switch to the wear leveling mode if it is detected that the erasing times of the physical block is greater than or equal to the first erasing threshold; and the data moving module 220, configured to The data of the first physical block and the data of the second physical block are moved and exchanged, wherein the erasing times of the first physical block is less than the first erasing threshold, and the erasing times of the second physical block is greater than the first erasing threshold.

The optional first erasing threshold is equal to the mean value of erasing times of multiple physical blocks in the storage module.

The optional data moving module is specifically used to determine the physical block with the smallest number of erasures among the multiple physical blocks as the first physical block, and determine the physical block with the largest number of erasures among the multiple physical blocks as the second physical block, and The data of the first physical block and the second physical block are exchanged.

Optionally, the control device further includes: a detection module configured to receive the first operation command and determine the physical block corresponding to the first operation command, and then detect whether the erasing times of the physical block is greater than or equal to the first erasing threshold.

In this embodiment, a deterministic algorithm is used to implement the wear leveling mechanism. The second physical block has a large number of erasures, indicating that the data of the second physical block is frequently updated to obtain more erasure opportunities, while the first physical block has a small number of erasures, indicating that the data of the first physical block is rarely updated. Rarely get erasing opportunities, exchange the data of the first physical block and the second physical block, then the frequently updated data is moved to the first physical block, which increases the erasing opportunities of the first physical block, and vice versa. The erasure opportunity is reduced, thereby reducing the difference in the number of erasures of at least two physical blocks in the storage device, achieving wear leveling, reducing the degree of physical block wear, and prolonging the service life of the device.

In the prior art, a randomness algorithm is used to implement a wear leveling mechanism, and specifically, a certain physical block is randomly selected for an erasing operation according to a uniform distribution probability. Regardless of whether the physical block contains "cold" data or "hot" data, let each physical block have an equal probability of being erased, and then copy the valid data in the original block to an empty block and erase the block. Obviously, the effect of this algorithm is greatly affected by random factors, and the number of erasures of each block cannot reach equal probability, so it cannot achieve a good wear balance effect.

In this embodiment, by this method, data is written into different physical blocks in the memory each time, so as to achieve balanced use of physical blocks, improve the service life of physical blocks on the device side, and maximize the use of physical blocks on the device , reducing the degree of wear and tear and extending the longest service life of the equipment.

Based on the same inventive concept, an embodiment of the present invention further provides a storage device, the storage device includes a storage module and the control device described in any of the above embodiments, and the control device is electrically connected to the storage module. The optional storage module is NAND Flash, and the storage device is SSD.

Note that the above are only preferred embodiments of the present invention and applied technical principles. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, combinations and substitutions can be made by those skilled in the art without departing from the protection scope of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and can also include more other equivalent embodiments without departing from the concept of the present invention. The scope is determined by the scope of the appended claims.

Claims (9)

1. A control method of a storage device, wherein the storage device includes a storage module, the storage module includes a plurality of physical blocks, the control method comprising:

if the number of times of erasing the physical block is detected to be larger than or equal to a first erasing threshold value, switching to a wear leveling mode;

and carrying out moving exchange on the data of the first physical block and the data of the second physical block, wherein the erasing times of the first physical block are smaller than the first erasing threshold value, and the erasing times of the second physical block are larger than the first erasing threshold value.

2. The method of claim 1, wherein the first erase threshold is equal to an average number of erases of a plurality of physical blocks in the memory module.

3. The control method according to claim 1, wherein the moving and exchanging the data of the first physical block and the data of the second physical block comprises:

and determining the physical block with the minimum erasing times in the plurality of physical blocks as the first physical block, determining the physical block with the maximum erasing times in the plurality of physical blocks as the second physical block, and exchanging data of the first physical block and the second physical block.

4. The method of claim 1, wherein before detecting that the number of times the physical block is erased is greater than or equal to a first erase threshold, the method further comprises:

receiving a first operation command, determining a physical block corresponding to the first operation command, and detecting whether the erasing times of the physical block is greater than or equal to the first erasing threshold.

5. A control apparatus of a storage device, wherein the storage device includes a storage module including a plurality of physical blocks, the control apparatus comprising:

the mode switching module is used for switching to a wear leveling mode if the fact that the erasing times of the physical block are larger than or equal to a first erasing threshold value is detected;

and the data moving module is used for moving and exchanging the data of the first physical block and the data of the second physical block, wherein the erasing times of the first physical block are less than the first erasing threshold, and the erasing times of the second physical block are greater than the first erasing threshold.

6. The control device of claim 5, wherein the first erase threshold is equal to an average number of erases of a plurality of physical blocks in the memory module.

7. The control device according to claim 5, wherein the data moving module is specifically configured to determine a physical block with a smallest number of times of erasure from among the plurality of physical blocks as the first physical block, determine a physical block with a largest number of times of erasure from among the plurality of physical blocks as the second physical block, and exchange data of the first physical block and the second physical block.

8. The control device according to claim 5, characterized by further comprising:

the detection module is used for receiving a first operation command, determining a physical block corresponding to the first operation command, and then detecting whether the erasing times of the physical block is larger than or equal to the first erasing threshold.

9. A memory device, characterized in that the memory device comprises a memory module and a control means according to any of claims 5-8, which control means is electrically connected to the memory module.

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