Mapping compression method and device based on mapping fragment compression mark and computer equipment

Abstract

The invention relates to a mapping compression method and device based on a mapping fragment compression mark, computer equipment and a storage medium, and the method comprises the steps: judging whether the current mapping meets a preset compression rule or not in the process of generating a mapping fragment; according to the judgment result, generating a corresponding compression mark for marking whether the mapping fragment is compressible or not; only storing non-compression format mapping in the process of writing the mapping fragments into the NAND, and storing corresponding compression marks into metadata of the mapping fragments at the same time; and when a new mapping fragment needs to be loaded, storing the mapping fragment into the RAM in a non-compression format, and reading the corresponding compression mark to judge whether the mapping fragment is compressible or not. According to the method, the persistence of the compressed information can be realized, the mapping storage format in the NAND is simplified, the conversion between the compressed format and the non-compressed format is reduced, and the SSD performance is further improved.

Description

Technical Field

[0001] The present invention relates to the technical field of solid state hard disks, and in particular to a mapping compression method, device, computer equipment and storage medium based on mapping slice compression marking. Background Art

[0002] SSD (Solid State Drive) is a new type of storage medium that uses NAND particles as data storage. It has been widely used in various fields such as PCs, notebooks, and servers, and has gradually replaced HDD (Hard Disk Drive) to become the mainstream application product in the storage field.

[0003] Since the internal RAM space of DRAM-less SSD is small, in order to store more mappings in the limited RAM, the mapping table with specific rules is usually compressed and stored in NAND in a compressed format. In traditional technical means, the mapping stored in NAND in a compressed format is not only complex to manage, but also always stored in RAM in a compressed format, which has an adverse effect on the efficiency of mapping table query. Alternatively, in order to avoid the complexity of the above-mentioned compressed mapping management in NAND, only the compressed information is saved in RAM. In this solution, the compressed information is lost after power failure. Summary of the invention

[0004] Based on this, it is necessary to provide a mapping compression method, device, computer equipment and storage medium based on mapping fragment compression marking to address the above technical problems.

[0005] A mapping compression method based on mapping fragment compression marking, the method comprising:

[0006] In the process of generating mapping fragments, determine whether the current mapping meets the preset compression rules;

[0007] Generate a corresponding compression mark based on the judgment result to mark whether the mapping fragment is compressible;

[0008] When writing the mapping slice into NAND, only the uncompressed format mapping is stored, and the corresponding compression mark is also stored in the metadata of the mapping slice;

[0009] When a new mapping segment needs to be loaded, the mapping segment is stored in the RAM in an uncompressed format and the corresponding compression flag is read to determine whether the mapping segment is compressible.

[0010] In one embodiment, the method further comprises:

[0011] During the mapping update process of the mapping shard, check whether the updated mapping satisfies the preset compression rule;

[0012] If the preset compression rule is not satisfied, the mapping slice is marked as incompressible;

[0013] After the mapping of the entire mapping slice is updated, if all updated mappings meet the preset compression rule, the mapping slice is marked as compressible.

[0014] In one embodiment, the method further comprises:

[0015] When the mapping cache needs to be released, check whether the mapping slice to be released is compressible according to the compression mark;

[0016] If compression is not possible, the mapping slice is directly deleted from the mapping cache;

[0017] If compression is possible, the map slices are converted from uncompressed format to compressed format and stored in a compressed map slice cache so that as many maps as possible can be stored in RAM.

[0018] In one embodiment, the step of converting the mapping slice from an uncompressed format to a compressed format and storing the mapping slice in a compressed mapping slice cache if compression is possible further comprises:

[0019] Determine whether the current compression map shard cache is full;

[0020] If the current compressed map segment cache is full, the compressed map cache that has not been used for the longest time is released and then a compressed map cache space is allocated.

[0021] A mapping compression device based on mapping fragment compression mark, the device comprising:

[0022] A judgment module, wherein the judgment module is used to judge whether the current mapping satisfies a preset compression rule during the process of generating the mapping fragments;

[0023] A generation module, the generation module is used to generate a corresponding compression mark according to the judgment result to mark whether the mapping slice is compressible;

[0024] A writing module, wherein the writing module is used to store only the uncompressed format mapping during the process of writing the mapping slice into NAND, and simultaneously store the corresponding compression mark in the metadata of the mapping slice;

[0025] The reading module is used to store the mapping slice in an uncompressed format in the RAM and read the corresponding compression mark to determine whether the mapping slice is compressible when a new mapping slice needs to be loaded.

[0026] In one embodiment, the device is further used for:

[0027] During the mapping update process of the mapping shard, check whether the updated mapping satisfies the preset compression rule;

[0028] If the preset compression rule is not satisfied, the mapping slice is marked as incompressible;

[0029] After the mapping of the entire mapping slice is updated, if all updated mappings meet the preset compression rule, the mapping slice is marked as compressible.

[0030] In one embodiment, the device further comprises a release module, wherein the release module is configured to:

[0031] When the mapping cache needs to be released, check whether the mapping slice to be released is compressible according to the compression mark;

[0032] If compression is not possible, the mapping slice is directly deleted from the mapping cache;

[0033] If compression is possible, the map slices are converted from uncompressed format to compressed format and stored in a compressed map slice cache so that as many maps as possible can be stored in RAM.

[0034] In one embodiment, the release module is further used for:

[0035] Determine whether the current compression map shard cache is full;

[0036] If the current compressed map segment cache is full, the compressed map cache that has not been used for the longest time is released and then a compressed map cache space is allocated.

[0037] A computer device comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of any one of the above methods when executing the computer program.

[0038] A computer-readable storage medium stores a computer program, wherein the computer program implements the steps of any one of the above methods when executed by a processor.

[0039] The mapping compression method, device, computer equipment and storage medium based on mapping slice compression mark are as follows: in the process of generating mapping slices, whether the current mapping satisfies the preset compression rules is judged; according to the judgment result, a corresponding compression mark is generated to mark whether the mapping slice is compressible; in the process of writing the mapping slice into NAND, only the non-compressed format mapping is stored, and the corresponding compression mark is stored in the metadata of the mapping slice at the same time; when a new mapping slice needs to be loaded, the mapping slice is stored in RAM in non-compressed format and the corresponding compression mark is read to judge whether the mapping slice is compressible. In the present invention, only non-compressed format mapping is stored in NAND, but the compression mark of whether each mapping page can be compressed is also stored in the metadata corresponding to the mapping page, and in RAM, the mapping slice can be stored in compressed or non-compressed format according to the scenario, so that the persistence of compressed information can be achieved, and the mapping storage format in NAND is simplified, and the conversion between compressed and non-compressed formats is reduced, thereby improving the performance of SSD. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 A schematic diagram of a flow chart of a mapping compression method based on mapping fragment compression marks in one embodiment;

[0041] Figure 2 It is a flowchart of a mapping compression method based on mapping fragment compression mark in another embodiment;

[0042] Figure 3 A schematic diagram of a process for generating and storing a compressible mark in one embodiment;

[0043] Figure 4 A schematic diagram of a process of compressing a mapping table in one embodiment;

[0044] Figure 5 is a structural block diagram of a mapping compression device based on mapping fragment compression marks in one embodiment;

[0045] Figure 6 It is a structural block diagram of a mapping compression device based on mapping fragment compression mark in another embodiment;

[0046] Figure 7 FIG. 4 is a diagram showing the internal structure of a computer device in one embodiment. DETAILED DESCRIPTION

[0047] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0048] At present, due to the small internal RAM space of DRAM-less SSD, in order to store more mappings in the limited RAM, the mapping table with specific rules is usually compressed and stored in NAND in a compressed format. In traditional technical means, the mapping stored in NAND in a compressed format is not only complex to manage, but also always stored in RAM in a compressed format, which has an adverse effect on the efficiency of mapping table query. Or, in order to avoid the complexity of the above-mentioned compressed mapping management in NAND, only the compressed information is saved in RAM. In this solution, the compressed information is lost after power failure.

[0049] Based on this, the present invention provides a mapping compression method based on mapping fragment compression marking, aiming to improve the efficiency of compression mapping management and thus improve SSD performance.

[0050] In one embodiment, Figure 1 As shown, a mapping compression method based on mapping fragment compression mark is provided, and the method includes:

[0051] Step 102, in the process of generating mapping fragments, determining whether the current mapping satisfies the preset compression rule;

[0052] Step 104, generating a corresponding compression mark according to the judgment result to mark whether the mapping slice is compressible;

[0053] Step 106, in the process of writing the mapping slice into NAND, only the uncompressed format mapping is stored, and the corresponding compression mark is simultaneously stored in the metadata of the mapping slice;

[0054] Step 108, when a new mapping segment needs to be loaded, the mapping segment is stored in the RAM in an uncompressed format and the corresponding compression flag is read to determine whether the mapping segment is compressible.

[0055] In this embodiment, a mapping compression method based on mapping slice compression mark is provided. Only non-compressed format mapping is stored in NAND, but the mark of whether each mapping page can be compressed is also stored in the metadata corresponding to the mapping page; in RAM, the mapping slice can be stored in compressed or non-compressed format according to the scenario. In this way, the persistence of compressed information (i.e., no loss during power failure) can be achieved, and the mapping storage format in NAND can be simplified, reducing the conversion between compressed and non-compressed formats and improving system performance.

[0056] Specifically, in the process of generating the mapping fragment, it is determined whether the current mapping satisfies the preset compression rule, and a corresponding compression mark is generated according to the determination result to mark whether the mapping fragment is compressible.

[0057] When writing mapping segments to NAND, only the uncompressed format mapping is stored, and the corresponding compression mark is also stored in the metadata of the mapping segment. Only the uncompressed format mapping is stored in NAND, but the mark of whether each mapping page can be compressed is also stored in the metadata corresponding to the mapping page; in RAM, the mapping segments can be stored in compressed or uncompressed format according to the scenario.

[0058] In the process of generating mapping shards, whether the mapping shard is compressible is marked according to whether the mapping meets specific rules (such as rules that mappings within the shard are arranged sequentially). In the process of writing the mapping shards to NAND, this compression mark is also stored in the metadata corresponding to the mapping page.

[0059] When a new mapping page needs to be loaded, the mapping page is stored in RAM in an uncompressed format, and the flag indicating whether the mapping slice can be compressed is also read into RAM. In addition, when an old mapping slice needs to be replaced, it is first checked whether the old mapping slice can be compressed. If it can be compressed, the mapping slice is converted to a compressed format and placed in RAM, freeing up the mapping cache space it occupies.

[0060] In this embodiment, during the process of generating a mapping slice, it is determined whether the current mapping satisfies the preset compression rules; a corresponding compression mark is generated according to the determination result to mark whether the mapping slice is compressible; during the process of writing the mapping slice into NAND, only the non-compressed format mapping is stored, and the corresponding compression mark is simultaneously stored in the metadata of the mapping slice; when a new mapping slice needs to be loaded, the mapping slice is stored in RAM in non-compressed format and the corresponding compression mark is read to determine whether the mapping slice is compressible. In the present invention, only non-compressed format mapping is stored in NAND, but the compression mark of whether each mapping page can be compressed is also stored in the metadata corresponding to the mapping page, and the mapping slice in RAM can be stored in compressed or non-compressed format according to the scenario, which can not only realize the persistence of compressed information, but also simplify the mapping storage format in NAND, reduce the conversion between compressed and non-compressed formats, and thus improve the performance of SSD.

[0061] In one embodiment, Figure 2 As shown, a mapping compression method based on mapping fragment compression mark is provided, and the method also includes:

[0062] Step 202, during the mapping update process of the mapping slice, checking whether the updated mapping satisfies the preset compression rule;

[0063] Step 204: if the preset compression rule is not satisfied, then mark the mapping slice as incompressible;

[0064] Step 206: After the mapping of the entire mapping slice is updated, if all updated mappings meet the preset compression rule, the mapping slice is marked as compressible.

[0065] Specifically, please refer to Figure 3 The schematic diagram of the process of generating and storing the compressible mark shown in FIG. 1 is a schematic diagram of the process of generating and storing the compressible mark, and the specific implementation steps are as follows:

[0066] The compression mark of the mapping shard is generated along with the mapping update process of the mapping shard: when the first mapping of the mapping shard is updated, a record is created to identify whether the mapping shard is compressible. In the subsequent mapping update process of the mapping shard, it is checked whether the newly updated mapping meets the compression rule requirements. If not, the mapping shard is marked as incompressible. After the mapping of the entire mapping shard is updated, if all updated mappings meet the compression rules, the mapping shard is marked as compressible. When saving the mapping shard to NAND, the compressible mark is stored in the metadata corresponding to the mapping page.

[0067] In addition, if there is no record identifying whether the mapping fragment is compressible when a mapping update request is received, and the mapping fragment previously had a compressible mark, the compressible mark of the mapping fragment will be cleared first.

[0068] In one embodiment, a mapping compression method based on mapping fragment compression marking is provided, the method further comprising:

[0069] When the mapping cache needs to be released, check whether the mapping slice to be released is compressible according to the compression mark;

[0070] If compression is not possible, the mapping slice is directly deleted from the mapping cache;

[0071] If compression is possible, the mapping slice is converted from an uncompressed format to a compressed format and stored in a compressed mapping slice cache so that as many mappings as possible can be stored in RAM;

[0072] Determine whether the current compression map shard cache is full;

[0073] If the current compressed map segment cache is full, the compressed map cache that has not been used for the longest time is released and then a compressed map cache space is allocated.

[0074] Specifically, please refer to Figure 4 The flowchart of mapping table compression shown in the figure is as follows:

[0075] When the mapping table is loaded from NAND to the mapping cache due to a read or write request, it will exist in an uncompressed format, so that a more efficient mapping table search efficiency can be maintained; when the mapping cache needs to be released, it will first check whether the mapping slice is compressible. If it can be compressed, it will be converted from an uncompressed format to a compressed format and stored in a compressed mapping slice cache, so that as many mappings as possible can be stored in RAM.

[0076] In the above embodiment, mapping compression information is managed by mapping slices, and non-compressed mapping is always stored in NAND. At the same time, whether to compress the mapping slice is postponed to the time point when the mapping slice is about to be mapped. This can not only achieve the persistence of compressed information, but also simplify the mapping storage format in NAND, reduce the conversion between compressed and non-compressed formats, and improve system performance.

[0077] It should be understood that although Figure 1-Figure 4 The steps in the flowchart are shown in sequence as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified in this document, there is no strict order restriction for the execution of these steps, and these steps can be executed in other orders. Moreover, Figure 1-Figure 4 At least part of the steps may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least part of the sub-steps or stages of other steps.

[0078] In one embodiment, Figure 5 As shown, a mapping compression device 500 based on mapping fragment compression mark is provided, and the device includes:

[0079] A judgment module 501, which is used to judge whether the current mapping satisfies a preset compression rule during the process of generating mapping fragments;

[0080] A generation module 502, the generation module is used to generate a corresponding compression mark according to the judgment result to mark whether the mapping slice is compressible;

[0081] A writing module 503, which is used to store only the uncompressed format mapping during the process of writing the mapping slice into NAND, and store the corresponding compression mark in the metadata of the mapping slice at the same time;

[0082] The reading module 504 is used to store the mapping fragment in the RAM in an uncompressed format and read the corresponding compression mark to determine whether the mapping fragment is compressible when a new mapping fragment needs to be loaded.

[0083] In one embodiment, the device is also used to:

[0084] During the mapping update process of the mapping shard, check whether the updated mapping satisfies the preset compression rule;

[0085] If the preset compression rule is not satisfied, the mapping slice is marked as incompressible;

[0086] After the mapping of the entire mapping slice is updated, if all updated mappings meet the preset compression rule, the mapping slice is marked as compressible.

[0087] In one embodiment, Figure 6 As shown, a mapping compression device 500 based on mapping fragment compression mark is provided, and the device also includes a release module 505, which is used to:

[0088] When the mapping cache needs to be released, check whether the mapping slice to be released is compressible according to the compression mark;

[0089] If compression is not possible, the mapping slice is directly deleted from the mapping cache;

[0090] If compression is possible, the map slices are converted from uncompressed format to compressed format and stored in a compressed map slice cache so that as many maps as possible can be stored in RAM.

[0091] In one embodiment, the release module 505 is further configured to:

[0092] Determine whether the current compression map shard cache is full;

[0093] If the current compressed map segment cache is full, the compressed map cache that has not been used for the longest time is released and then a compressed map cache space is allocated.

[0094] The specific limitations on the mapping compression device based on mapping fragment compression marks can be found in the above limitations on the mapping compression method based on mapping fragment compression marks, which will not be repeated here.

[0095] In one embodiment, a computer device is provided, whose internal structure diagram can be as follows: Figure 7As shown. The computer device includes a processor, a memory and a network interface connected through a device bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating device, a computer program and a database. The internal memory provides an environment for the operation of the operating device and the computer program in the non-volatile storage medium. The network interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, a mapping compression method based on mapping fragment compression tags is implemented.

[0096] Those skilled in the art will understand that Figure 7 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0097] In one embodiment, a computer device is provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor implements the steps in the above method embodiments when executing the computer program.

[0098] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps in the above method embodiments are implemented.

[0099] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in the present application can include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

[0100] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0101] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

Claims

1. A mapping compression method based on mapping fragment compression marking, the method comprising: In the process of generating mapping fragments, determine whether the current mapping meets the preset compression rules; Generate a corresponding compression mark based on the judgment result to mark whether the mapping fragment is compressible; When writing the mapping slice into NAND, only the uncompressed format mapping is stored, and the corresponding compression mark is also stored in the metadata of the mapping slice; When a new mapping segment needs to be loaded, the mapping segment is stored in the RAM in an uncompressed format and the corresponding compression flag is read to determine whether the mapping segment is compressible.

2. The mapping compression method based on mapping fragment compression mark according to claim 1 is characterized in that: The method further comprises: During the mapping update process of the mapping shard, check whether the updated mapping satisfies the preset compression rule; If the preset compression rule is not satisfied, the mapping slice is marked as incompressible; After the mapping of the entire mapping slice is updated, if all updated mappings meet the preset compression rule, the mapping slice is marked as compressible.

3. The mapping compression method based on mapping fragment compression mark according to claim 1 is characterized in that: The method further comprises: When the mapping cache needs to be released, check whether the mapping slice to be released is compressible according to the compression mark; If compression is not possible, the mapping slice is directly deleted from the mapping cache; If compression is possible, the map slices are converted from uncompressed format to compressed format and stored in a compressed map slice cache so that as many maps as possible can be stored in RAM.

4. The mapping compression method based on mapping fragment compression mark according to claim 3 is characterized in that: The step of converting the mapping slice from an uncompressed format to a compressed format and storing the mapping slice in a compressed mapping slice cache if the mapping slice can be compressed also includes: Determine whether the current compression map shard cache is full; If the current compressed map segment cache is full, the compressed map cache that has not been used for the longest time is released and then a compressed map cache space is allocated.

5. A mapping compression device based on mapping fragment compression mark, characterized in that: The device comprises: A judgment module, wherein the judgment module is used to judge whether the current mapping satisfies a preset compression rule during the process of generating the mapping fragments; A generation module, the generation module is used to generate a corresponding compression mark according to the judgment result to mark whether the mapping slice is compressible; A writing module, wherein the writing module is used to store only the uncompressed format mapping during the process of writing the mapping slice into NAND, and simultaneously store the corresponding compression mark in the metadata of the mapping slice; The reading module is used to store the mapping slice in an uncompressed format in the RAM and read the corresponding compression mark to determine whether the mapping slice is compressible when a new mapping slice needs to be loaded.

6. The mapping compression device based on mapping fragment compression mark according to claim 5, characterized in that: The device is also used for: During the mapping update process of the mapping shard, check whether the updated mapping satisfies the preset compression rule; If the preset compression rule is not satisfied, the mapping slice is marked as incompressible; After the mapping of the entire mapping slice is updated, if all updated mappings meet the preset compression rule, the mapping slice is marked as compressible.

7. The mapping compression device based on mapping fragment compression mark according to claim 5, characterized in that: The device further comprises a release module, wherein the release module is used for: When the mapping cache needs to be released, check whether the mapping slice to be released is compressible according to the compression mark; If compression is not possible, the mapping slice is directly deleted from the mapping cache; If compression is possible, the map slices are converted from uncompressed format to compressed format and stored in a compressed map slice cache so that as many maps as possible can be stored in RAM.

8. The mapping compression device based on mapping fragment compression mark according to claim 7, characterized in that: The release module is also used for: Determine whether the current compression map shard cache is full; If the current compressed map segment cache is full, the compressed map cache that has not been used for the longest time is released and then a compressed map cache space is allocated.

9. A computer device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 4 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 4 are implemented.

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