KR20190067147A - Method and apparatus for improving database recovery speed using log data analysis - Google Patents

Abstract

According to an aspect of the present invention, there is provided a method for improving database restoration speed using log data analysis, the method comprising: reading at least one redo log file, To a storage unit; Analyzing the stored restoration log data to generate a plurality of sublog data groups, each of the plurality of sublog data groups being associated with a specific data block and having a specific data block associated with each of the plurality of sublog data groups, Are different from each other; And generating at least one neighbor log data group based on location information of specific data blocks associated with each of the plurality of sub log data groups, wherein each of the at least one neighbor log data group includes at least one sub log data group And the like.
A second aspect of embodiments of the present invention is a database management server for providing a database recovery speed improvement method using log data analysis, the database management server comprising: a log file reading unit reading at least one redo log file; A data loading unit for loading recovery log data into a storage unit; A sub log data group generating unit for analyzing the restored log data and generating a plurality of sub log data groups, each of the plurality of sub log data groups being associated with a specific data block, each of the plurality of sub log data groups The specific data blocks associated with each other are different; And a neighbor log data group generating unit for generating at least one neighbor log data group based on position information of specific data blocks associated with each of the plurality of sub log data groups, And a sub-log data group of sub-log data.
A third aspect of embodiments of the present invention is a computer program stored in a computer-readable storage medium including encoded instructions, the computer program being executable by one or more processors of a computer system, Causing the processors to perform the following operations: reading at least one redo log file and loading recovery log data into the storage; Analyzing the restored log data to generate a plurality of sub log data groups, each of the plurality of sub log data groups being associated with a specific data block, and having a specific data block associated with each of the plurality of sub log data groups Are different from each other; And generating at least one contiguous log data group based on location information of specific data blocks associated with each of the plurality of sub log data groups, wherein each of the at least one contiguous log data group includes at least one sub log data group And the like.

Description

Technical Field [0001] The present invention relates to a method and apparatus for improving database recovery speed using log data analysis,

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a database recovery method, and more particularly, to a method and system for restoring a database using a data file and a redo log when a failure occurs in a database in which write- And to a method for efficiently proceeding.

Recovery from an existing database is performed by simply reading the redo log file to recover the database, selecting the data block to be restored based on the log, reading the block from the data file, and applying the redo log.

However, when the data file is read from the disk, the access to the randomly scattered block must be read to read the disk. In addition, if multiple redo logs are applied to one data block while the read data block is loaded in the memory cache, it is possible to access the disk unnecessarily many times to delay the entire recovery operation time. Also, when reading a data block, assuming that the address of one block is known, there is a problem that asynchronous input / output (AIO) can not be performed.

Therefore, there is a need for a method that can reduce the overall database recovery time by efficiently accessing the disk during database recovery.

Disclosure of Invention Technical Problem [8] The present invention has been devised in response to the background art described above, and is a method for improving database restoration speed using log data analysis, in order to reduce overall database recovery time by efficiently accessing a disk.

According to an aspect of the present invention, there is provided a method for improving database restoration speed using log data analysis, the method comprising: reading at least one redo log file, To a storage unit; Analyzing the stored restoration log data to generate a plurality of sublog data groups, each of the plurality of sublog data groups being associated with a specific data block and having a specific data block associated with each of the plurality of sublog data groups, Are different from each other; And generating at least one neighbor log data group based on location information of specific data blocks associated with each of the plurality of sub log data groups, wherein each of the at least one neighbor log data group includes at least one sub log data group And the like.

A second aspect of embodiments of the present invention is a database management server for providing a database recovery speed improvement method using log data analysis, the database management server comprising: a log file reading unit reading at least one redo log file; A data loading unit for loading recovery log data into a storage unit; A sub log data group generating unit for analyzing the restored log data and generating a plurality of sub log data groups, each of the plurality of sub log data groups being associated with a specific data block, each of the plurality of sub log data groups The specific data blocks associated with each other are different; And a neighbor log data group generating unit for generating at least one neighbor log data group based on position information of specific data blocks associated with each of the plurality of sub log data groups, And a sub-log data group of sub-log data.

A third aspect of embodiments of the present invention is a computer program stored in a computer-readable storage medium including encoded instructions, the computer program being executable by one or more processors of a computer system, Causing the processors to perform the following operations: reading at least one redo log file and loading recovery log data into the storage; Analyzing the restored log data to generate a plurality of sub log data groups, each of the plurality of sub log data groups being associated with a specific data block, and having a specific data block associated with each of the plurality of sub log data groups Are different from each other; And generating at least one contiguous log data group based on location information of specific data blocks associated with each of the plurality of sub log data groups, wherein each of the at least one contiguous log data group includes at least one sub log data group And the like.

According to an embodiment of the present invention, a database recovery speed improvement method using log data analysis can reduce the overall database recovery time by efficiently accessing the disk.

Various aspects are now described with reference to the drawings, wherein like reference numerals are used to refer to like elements throughout. In the following examples, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of one or more aspects. However, it will be apparent that such aspect (s) may be practiced without these specific details.
1 illustrates a database management system in accordance with an embodiment of the present invention.
FIG. 2 illustrates a step of improving the recovery speed of a database using log data sorting according to an embodiment of the present invention.
FIG. 3 illustrates internal components of a database management server according to an embodiment of the present invention.
4 illustrates a method of generating a sub log data group and a neighbor log data group by arranging recovery log data according to an embodiment of the present invention.
FIG. 5 illustrates a method for asynchronously acquiring a plurality of adjacent data blocks by a database management server according to an embodiment of the present invention.

Various embodiments and / or aspects are now described with reference to the drawings. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of one or more aspects. However, it will also be appreciated by those of ordinary skill in the art that such aspect (s) may be practiced without these specific details. The following description and the annexed drawings set forth in detail certain illustrative aspects of one or more aspects. It is to be understood, however, that such aspects are illustrative and that some of the various ways of practicing various aspects of the principles of various aspects may be utilized, and that the description set forth is intended to include all such aspects and their equivalents.

In addition, various aspects and features will be presented by a system that may include one or more devices, terminals, servers, devices, components and / or modules, and the like. It is to be understood and appreciated that the various systems may include additional devices, terminals, servers, devices, components and / or modules, and / or devices, terminals, It should also be understood and appreciated that the present invention may not include all of the devices, components, modules, and the like.

As used herein, the terms "an embodiment," "an embodiment," " an embodiment, "" an embodiment ", etc. are intended to indicate that any aspect or design described is better or worse than other aspects or designs. . As used herein, the terms 'component', 'module', 'system', 'interface' and the like generally refer to a computer-related entity such as a combination of hardware, , ≪ / RTI > or software.

In addition, the term "or" is intended to mean " exclusive or " That is, it is intended to mean one of the natural inclusive substitutions "X uses A or B ", unless otherwise specified or unclear in context. That is, X uses A; X uses B; Or when X uses both A and B, "X uses A or B" can be applied to either of these cases. It should also be understood that the term "and / or" as used herein refers to and includes all possible combinations of one or more of the listed related items.

It is also to be understood that the term " comprises "and / or" comprising " means that the feature and / or component is present, but does not exclude the presence or addition of one or more other features, components and / It should be understood that it does not. Also, unless the context clearly dictates otherwise or to the contrary, the singular forms in this specification and claims should generally be construed to mean "one or more. &Quot;

The computer readable media herein may include any type of storage medium in which programs and data are stored so that they can be read by a computer system. The computer-readable medium in the present disclosure may comprise a computer-readable storage medium and a computer-readable transmission medium. According to one aspect of the present invention, a computer-readable storage medium includes at least one of a ROM (Read Only Memory), a RAM (Random Access Memory), a CD (Compact Disk) Disks, optical data storage devices, and the like. In addition, the computer-readable medium may comprise any form of transferable medium embodied in the form of a carrier wave (e.g., transmission over the Internet). Additionally, such computer-readable media may be distributed over a networked system and may store computer readable codes and / or instructions in a distributed manner.

Before describing the embodiments of the present invention in detail, it is to be understood that the present invention is not limited to the above-described embodiments, but may be modified and changed without departing from the scope and spirit of the invention. It is also to be understood that the terminology or words used in the present specification and claims should be interpreted with reference to the meaning of the inventive concept of the present invention based on the principle that the inventor can define the concept of appropriate terms to describe his invention in the best way It should be interpreted as a concept.

As used herein, a database refers to a system that stores data related to each other in a form that can be processed by a computer. A database can store data and answer user questions, and data stored in the database can be changed. The database can store new data, and can delete existing data and modify it.

In this specification, the redo log file refers to a file that collects and records information (log data) necessary for recovery when a failure occurs in the database. The redo log file may be read from the database management server and may include recovery log data.

In this specification, log data refers to data in which contents related to data changes are recorded, such as a change of transaction or operational information during database operation.

The types of recovery performed using the log data include media recovery used for database recovery when a physical disk is damaged due to a media failure, a transaction when an instance is abnormally terminated, And Instance Recovery to prevent data loss, and the like, but the present invention is not limited thereto.

The log data may include various information about at least one data block.

For example, the log data may include information on the point of change of the data block. For example, the log data may include information about at what point a particular data block has changed.

Also, the log data may include the recording time information of the data block. For example, the log data may include information indicating when a particular block of data was written to the persistent storage medium 3000.

The log data may also include location information of the data block. Here, the location information may include various information that can identify the location of the data block. For example, it may include block address information indicating which part of a specific data block is recorded in the persistent storage medium 3000, and may include various information.

In this specification, a block may mean a chunk of data. For example, a block may include one table in which data is stored, and may include a plurality of tables. Further, the data included in one table can be represented by a plurality of blocks.

Blocks can have various sizes. For example, a block may have a size of 10 kb, 100 kb, 1 megabyte, 2 megabytes, 3 megabytes, 4 megabytes, and the like, but is not limited thereto.

Hereinafter, embodiments according to the present invention will be described in detail with reference to the accompanying drawings.

1 illustrates a database management system in accordance with an embodiment of the present invention.

According to one embodiment of the present invention, the database management system may include a database management server 1000, a network 2000, and a persistent storage medium 3000.

The database management server 1000 may include any type of computer system or computer device, such as a microprocessor, a mainframe computer, a digital single processor, a portable device, and a device controller.

The database management server 1000 may include a storage unit 200. The database management server 1000 can perform database recovery using the storage unit 200. [ For example, when the database management server 1000 reads the redo log file, the recovery log data is loaded on at least a part of the storage unit 200, specific data blocks are read from the persistent storage medium 3000, (200). ≪ / RTI > The recovery log data may be applied to specific data blocks stored in the storage unit 200.

The storage unit 200 is a main storage device directly accessed by the control unit 100, such as a random access memory (RAM) such as a dynamic random access memory (DRAM) or a static random access memory (SRAM) But is not limited to, a volatile storage device in which stored information is momentarily erased when the power is turned off. The storage unit 200 may be controlled by the control unit 100.

The database management server 1000 and the persistent storage medium 3000 can exchange data through the network 2000. Network 2000 may include, but is not limited to, a wired network, a wireless network.

The persistent storage medium 3000 may include a non-volatile storage medium capable of continuously storing any data. For example, the persistent storage medium 3000 may include storage devices based on flash memory and / or battery-backed memory as well as disks, optical disks, and magneto-optical storage devices, It is not limited.

The database management server 1000 can read at least one redo log file and load the recovery log data into the storage unit 200. [ Then, the database management server 1000 may analyze the restored log data and arrange the restoration log data for each specific data block associated with the respective recovery log data. The database management server 1000 may obtain certain data blocks from the persistent storage medium 3000 based on the aligned recovery log data. The recovery log data sorted in each of the specific data blocks acquired by the database management server 1000 can be sequentially applied to recover. In this case, the recovery log data applied to each of the specific data blocks may be associated with each of the specific data blocks.

Here, the database management server 1000 can acquire adjacent data blocks at a time based on the positional information of each data block associated with the aligned recovery log data. In this case, since the database management server 1000 obtains the specific data blocks adjacent to each other, rather than acquiring them, the number of times of accessing the persistent storage medium 3000 may be reduced.

In addition, the database management server 1000 may obtain data blocks from the persistent storage medium 3000 asynchronously. When the database management server 1000 acquires the data blocks asynchronously, it can utilize the maximum bandwidth provided by the persistent storage medium 3000, thereby reducing the database recovery time.

When the database management server 1000 acquires data blocks in a synchronous manner from the persistent storage medium 3000, the data is read from the persistent storage medium 3000 until the read operation for one data block is completed in the persistent storage medium 3000 Read requests may be limited. Thus, the database management server 1000 remains idle until the read operation is completed in the persistent storage medium 3000 to acquire the data block.

However, according to an embodiment of the present invention, when the database management server 1000 acquires data blocks in an asynchronous manner, the data stored in the persistent storage medium 3000 may include other data Read requests for blocks can be stacked and queued. That is, the operation of recovering the data block acquired by the database management server 1000 and the operation of reading the data blocks in the permanent storage medium 3000 may be performed independently.

When the time required for the input / output process (the process of requesting and acquiring data in the database restoration process) to the persistent storage medium 3000 is longer than the data processing time, the method of acquiring data blocks asynchronously reduces the database recovery time .

The components of the database management system shown in Fig. 1 are not limited to the above-described embodiments.

FIG. 2 illustrates a step of improving the recovery speed of a database using log data sorting according to an embodiment of the present invention.

According to an embodiment of the present invention, the database management server 1000 reads at least one log file and loads the recovery log data into the storage unit 200 (S110), analyzes the loaded recovery log data Generating a plurality of sub log data groups (S120), generating at least one adjacent log data group based on position information of specific data blocks associated with each of the plurality of sub log data groups (S130) (S140) of acquiring specific data blocks associated with a plurality of sub log data groups, loading (S150) the acquired specific data blocks in the storage unit (200) (S160) of applying the sub log data of the sub log data group of FIG.

In step S110, the database management server 1000 may read at least one log file and load the recovery log data into the storage unit 200. [ For example, the database management server 1000 may detect a redo log file necessary for database recovery from the entire log file set stored in the persistent storage medium 3000. [ The database management server 1000 may collect recovery log data necessary for database recovery from the redo log file and load the recovery log data into the storage unit 200.

In step S120, the database management server 1000 may generate a plurality of sub log data groups by analyzing the restored log data.

According to an embodiment of the present invention, the database management server 1000 can distinguish the recovery log data stored in the storage unit 200 by the associated specific data blocks. Then, a plurality of sub log data groups can be generated based on the classification result. Here, each of the plurality of sub log data groups may include sub log data.

For example, the database management server 1000 can classify the recovery log data stored in the storage unit 200 into data blocks of "block address: 1" and data blocks of "block address: 2" have. Then, based on the divided recovery log data, two sub log data groups can be created. In this case, each of the two sub log data groups may include sub log data.

In this case, the database management server 1000 may arrange the sub log data of the sub log data group in order of change time of the associated specific data block.

For example, the database management server 1000 may sort the sublog data in order of change time of a specific data block associated with the sublog data. The sublog data can be sequentially applied to a specific data block by sorting.

According to one embodiment of the present invention, each of the plurality of sublog data groups is associated with a specific data block, and the specific data blocks associated with each of the plurality of sublog data groups may be different from each other. When a sub log data group and a specific data block are associated, the entire sub log data of the sub log data group may include a change history for a specific data block.

For example, the specific data block associated with the first sub log data group may refer to a data block with location information of " block address: 1 ", in which case the entire sub log data of the first sub log data group & Block address: 1 ". The specific data block associated with the second sub log data group may refer to a data block whose location information is " block address: 2 ", and the entire sub log data of the second sub log data group is referred to as "Lt; / RTI > As described above, the sublog data of the first sub log data group and the second sub log data group may be different from the address information of the data block to be applied.

The database management server 1000 may generate a plurality of sublog data groups so that the associated data blocks can arrange the same sublog data.

In step S130, the database management server 1000 may generate at least one neighbor log data group based on the location information of the specific data blocks associated with each of the plurality of sub log data groups.

According to an embodiment of the present invention, the database management server 1000 may analyze location information of specific data blocks associated with a plurality of sublog data groups. Based on the analysis result, the database management server 1000 can identify a plurality of specific sub log data groups in which the positions of the associated specific data blocks are adjacent to each other. The database management server 1000 may generate at least one adjacent log data group based on the identification result.

For example, the database management server 1000 analyzes location information of specific data blocks associated with the five sub log data groups, and stores the sub log data group (" block address: " 1, " a sublog data group associated with a data block, " a block address: 2 "). In addition, adjacent log data groups can be created with the two sub log data groups. In this case, the database management server 1000 retrieves specific data blocks (a data block with a "block address: 1", a data block with a "block address: 2") associated with an adjacent log data group from the persistent storage medium 3000 Can be obtained at the same time.

According to one embodiment of the invention, the presence of at least two specific data blocks in the persistent storage medium 3000 may include that the distance between at least two specific data blocks is less than a predetermined distance. For example, the database management server 1000 may determine a location based on location information of at least two specific data blocks, and may compare the distance between at least two specific data blocks with a predetermined distance. And, if the distance between at least two specific data blocks is shorter than the predetermined distance, the database management server 1000 can determine that at least two specific data blocks are adjacent to each other. Here, the predetermined distance may be predetermined by the database management server 1000. [

In addition, according to another embodiment of the present invention, at least two specific data blocks are contiguous in the persistent storage medium 3000, meaning that the database management server 1000 receives the particular data And that the distance between particular data blocks is close enough to obtain the blocks.

For example, if the specific data block associated with the first sublog data group is "block address: 1" and the particular data block associated with the second sublog data group is "block address: 2", the database management server 1000 May determine the location of specific data blocks within the persistent storage medium 3000 based on the location information of the specific data blocks. If it is determined that the specific data blocks can be acquired from the persistent storage medium in one attempt, the database management server 1000 may determine that the first sub log data group and the second sub log data group are adjacent. The database management server 1000 may generate the first neighbor log data group including the adjacent first sub log data group and the second sub log data group.

According to an embodiment of the present invention, the database management server 1000 may arrange at least one adjacent log data group. For example, when the first adjacent log data group includes the first sub log data group and the fifth sub log data group, the first sub log data group and the fifth sub log data group may be stored in at least a part of the storage unit 200. For example, You can sort data groups side by side. In this case, based on the first sub log data group and the fifth sub log data group, which are stored in parallel in at least a part of the storage unit 200, the database management server 1000 transmits a specific data block Can be requested at one time. Accordingly, when the database management server 1000 arranges at least one adjacent log data group, the number of times the database management server 1000 accesses the persistent storage medium 3000 can be reduced.

In step S140, the database management server 1000 may acquire specific data blocks associated with a plurality of sublog data groups.

According to an embodiment of the present invention, the database management server 1000 may acquire specific data blocks associated with a plurality of sublog data groups from the persistent storage medium 3000.

For example, the database management server 1000 may obtain the A data block associated with the first sublog data group from the persistent storage medium 3000.

According to an embodiment of the present invention, the database management server 1000 may acquire specific data blocks located adjacent to each other in the persistent storage medium 3000 at a time.

For example, in the first adjacent log data group, the first sub log data group (the position information of the associated specific data block is " 1 ") and the second sub log data group (Block address: 2 ") is included, the database management server 1000 determines that the specific data blocks associated with the first neighbor log data group (the data block whose location information is " Block address: 2 ") from the persistent storage medium 3000 at one time.

In step S150, the database management server 1000 may load the acquired specific data blocks in the storage unit 200. [

According to an embodiment of the present invention, the database management server 1000 can load specific data blocks required to be restored in the storage unit 200 and apply the sub log data to the specific data blocks to be restored have.

In step S160, the database management server 1000 may apply the sub log data of the plurality of sub log data groups to the specific data blocks loaded.

According to an embodiment of the present invention, the database management server 1000 applies sub log data associated with specific data blocks of a plurality of sub log data groups to specific data blocks stored in the storage unit 200 . In this case, the sub log data may be stored in at least a part of the storage unit 200 in the order of change time of the associated data block.

For example, if an A data block is stored in the storage unit 200, the sublog data of the first sub log data group associated with the A data block may be applied to the A data block of the storage unit 200. Since the sub log data is stored in the order of changing time of the A data block, it can be continuously applied to the A data block.

According to an embodiment of the present invention, the database management server 1000 may apply sub log data associated with specific data blocks of the adjacent log data group to the specific data blocks stored in the storage unit 200 . In this case, the sub log data may be stored in at least a part of the storage unit 200 in the order of change time of the associated data block.

For example, if the location information of the specific data blocks stored in the storage unit 200 is "block address: 1" or "block address: 2", the database management server 1000 stores the sorted sub log data Sublog data associated with a data block with a block address of " 1 " and sublog data associated with a data block with a " block address: 2 " Here, the sub log data may be arranged in order of change time of specific data blocks so as to be continuously applied to specific data blocks.

The above-described steps in Fig. 2 are merely examples for explaining the present invention, but the present invention is not limited thereto. Also, at least one of the steps may be omitted or added.

The various embodiments described herein may be implemented in storage media and storage media readable by a computer or similar device using, for example, software, hardware, or a combination thereof.

According to a hardware implementation, the embodiments described herein may be implemented as application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays May be implemented using at least one of a processor, controllers, micro-controllers, microprocessors, and other electronic units for performing other functions. In some cases, The embodiments described may be implemented by the control unit 100 itself.

According to a software implementation, embodiments such as the procedures and functions described herein may be implemented with separate software modules. Each of the software modules may perform one or more of the functions and operations described herein. Software code can be implemented in a software application written in a suitable programming language. The software code is stored in the storage unit 200 and can be executed by the control unit 100. [

FIG. 3 illustrates internal components of a database management server according to an embodiment of the present invention.

According to an embodiment of the present invention, the database management server 1000 may include a control unit 100, a storage unit 200, and a transmission / reception unit 300. The control unit 100 includes a log file reading unit 110, a data loading unit 120, a sub log data group generating unit 130, an adjacent log data group generating unit 140, and a log data applying unit 150 .

The log file reading unit 110 can read at least one log file. Here, reading the log file may include detecting a redo log file necessary for recovery from the entire log file of the persistent storage medium 3000 and analyzing the recovery log data of the redo log file.

The data loading unit 120 may load the recovery log data read from the log file reading unit 110 into the storage unit 200. [ In addition, the specific data blocks obtained from the persistent storage medium 3000 can be loaded into the storage unit 200. FIG.

The sub log data group generating unit 130 may generate a plurality of sub log data groups by analyzing the restoration log data loaded in the storage unit 200. [ The sublog data group includes sublog data, and each sublog data group can be associated with a specific data block. The specific data blocks associated with each of the plurality of sublog data groups may be different from each other.

When a sub log data group and a specific data block are associated, the entire sub log data of the sub log data group may include a change history for a specific data block.

For example, the specific data block associated with the first sub log data group may refer to a block of data whose location information is " block address: 1 ", and the entire sub log data of the first sub log data group is & Block address: 1 ". The specific data block associated with the second sub log data group may refer to a data block whose location information is " block address: 2 ", and the entire sub log data of the second sub log data group may include & : 2 ". As described above, the sublog data of the first sub log data group and the second sub log data group may be different from the (associated) data block to be applied.

The sub log data group generation unit 130 generates a plurality of sub log data groups so that the (associated) data blocks to be applied can sort the same sub log data.

According to an embodiment of the present invention, the sub log data group generation unit 130 may divide the recovery log data into the associated specific data blocks. The sub log data group generating unit 130 may generate a plurality of sub log data groups based on the result of the classification. In this case, each of the plurality of sub log data groups may include sub log data.

For example, the sub log data group generation unit 130 can distinguish log data, which is the specific data block A, from the restoration log data, and log data that is the specific data block B associated therewith. The divided log data can be grouped into a first sub log data group and a second sub log data group. In this case, the first sublog data group may be associated with the A data block, and the second sublog data group may be associated with the B data block.

According to an embodiment of the present invention, the sub log data group generation unit 130 may arrange the sub log data of the sub log data group in order of change time of the associated specific data block.

For example, when there is sub log data associated with the A data block, the sub log data group generator 130 may rearrange the sub log data in order of change time of the A data blocks. In this case, the log data application unit 150 may continuously apply the aligned sub log data to the A data block.

The adjacent log data group generating unit 140 may generate at least one adjacent log data group based on the location information of the specific data blocks associated with the sub log data sorted by the sub log data group generating unit 130 .

According to an embodiment of the present invention, the adjacent log data group generation unit 140 may analyze location information of specific data blocks associated with a plurality of sub log data groups. The adjacent log data group generating unit 140 may identify a plurality of specific sub log data groups adjacent to each other in the locations of the associated specific data blocks based on the analysis result. In this case, the adjacent log data group generating unit 140 may generate at least one adjacent log data group based on the identification result.

For example, when the adjacent log data group creation unit 140 determines the positions of the A data block, the B data block, and the C data block associated with the first sub log data group, the second sub log data group, Information can be analyzed. The adjacent log data group generation unit 140 may analyze the positions of the A data block, the B data block, and the C data block in the persistent storage medium 3000. The adjacent log data group generation unit 140 can identify a specific data block adjacent to each other based on the analysis result. If the A data block and the B data block are identified as being adjacent to each other, The first neighbor log data group can be generated from the first sub log data group and the second sub log data group.

According to one embodiment of the invention, the presence of at least two specific data blocks in the persistent storage medium 3000 may include that the distance between at least two specific data blocks is less than a predetermined distance. For example, the database management server 1000 may determine a location based on location information of at least two specific data blocks, and may compare the distance between at least two specific data blocks with a predetermined distance. And, if the distance between at least two specific data blocks is shorter than the predetermined distance, the database management server 1000 can determine that at least two specific data blocks are adjacent to each other. Here, the predetermined distance may be predetermined by the database management server 1000. [

Also, in accordance with another embodiment of the present invention, at least two specific data blocks are contiguous in the persistent storage medium 3000, meaning that the location of at least two specific data blocks may be moved from the persistent storage medium 3000 at one time Lt; RTI ID = 0.0 > certain data blocks. ≪ / RTI >

For example, when the location information of the specific data block associated with the first sub log data group is "block address: 1" and the location information of the specific data block associated with the second sub log data group is "block address: 2" , The adjacent log data group generation unit 140 may determine the location of specific data blocks in the persistent storage medium 3000 based on the location information of the specific data blocks. If it is possible to acquire specific data blocks from the persistent storage medium in one attempt, the adjacent log data group generating unit 140 generates the adjacent log data group to which the specific data blocks associated with the first sub log data group and the second sub log data group are adjacent . In this case, the adjacent log data group generating unit 140 may generate the first adjacent log data group including the adjacent first sub log data group and the second sub log data group.

According to an embodiment of the present invention, the adjacent log data group generation unit 140 may reduce the number of times of obtaining the data block from the permanent storage medium 3000 by rearranging the plurality of adjacent log data groups.

The log data application unit 150 continuously applies the sub log data stored in at least a portion of the storage unit 200 to the specific data blocks stored in at least a part of the storage unit 200, You can recover files. In this case, the sub log data may include a history of change for specific data blocks.

For example, if the location information of the specific data blocks stored in the storage unit 200 is "block address: 1" or "block address: 2", the database management server 1000 transmits the sorted sub log data The data block having the information "block address: 1" and the data block having the position information "block address: 2", respectively) can be successively applied to the data block to be recovered. In this case, the sub log data may be applied in order of change time of specific data blocks.

The database management server 1000 can perform database recovery using the storage unit 200. [ For example, when the log file reading unit 110 of the database management server 1000 reads the redo log file, the data loading unit 120 loads the recovery log data into at least a part of the storage unit 200, The sub log data group generating unit 130 and the adjacent log data group generating unit 140 may arrange the sub log data. The database management server 1000 may read a specific data block from the persistent storage medium 3000 via the transceiver 300 and store the specific data block in at least a part of the storage unit 200. [ The log data application unit 150 may apply the sub log data to specific data blocks stored in at least a part of the storage unit 200. [

The storage unit 200 is a main storage device directly accessed by the control unit 100, such as a random access memory (RAM) such as a dynamic random access memory (DRAM) or a static random access memory (SRAM) But is not limited to, a volatile storage device in which stored information is momentarily erased when the power is turned off. This storage unit can be controlled by the control unit 100. [

The transceiver unit 300 can transmit and receive data to and from the persistent storage medium 3000 through the network 2000. [ The transceiver unit 300 may acquire specific data blocks from the persistent storage medium 3000 and may transmit the recovered data blocks to the persistent storage medium 3000.

According to an embodiment of the present invention, the transceiver unit 300 may acquire specific blocks associated with a plurality of sublog data groups from the persistent storage medium 3000. The transceiver unit 300 can acquire specific blocks associated with at least one adjacent log data group from the persistent storage medium 3000 at a time.

For example, the transceiver 300 may acquire the A data block and the B data block associated with the first neighbor log data group from the persistent storage medium 3000 at a time, not twice.

According to an embodiment of the present invention, the transmitting and receiving unit 300 can acquire specific data blocks associated with a plurality of sublog data groups asynchronously.

For example, when the transmitting / receiving unit 300 acquires the A data block and the B data block, after acquiring the A data block and completing the data recovery operation, The next data block can be obtained.

The internal components of the database management server 1000 shown in FIG. 3 are not limited to the above-described elements and may include a log file reading unit 110 of the control unit 100, a data loading unit 120, The log data generating unit 140, and the log data applying unit 150 may be implemented as at least one processor.

4 illustrates a method of generating a sub log data group and a neighbor log data group by arranging recovery log data according to an embodiment of the present invention.

According to an embodiment of the present invention, the database management server 1000 may scan the redo log file of the persistent storage medium 3000 to acquire and store recovery log data. Then, the recovery log data may be analyzed, and the plurality of sublog data groups may be created based on the specific data block to which the recovery log data is to be applied. In addition, the database management server 1000 may generate a plurality of sub log data groups, and at least one adjacent log data group based on position information of specific data blocks associated with the plurality of sub log data groups.

According to an embodiment of the present invention, the database management server 1000 generates a plurality of sub log data groups, as in (500), when the recovery log data is stored in the position information (block address) of the associated specific data block May include those listed below. In this case, the same location information may include that the particular data blocks associated with the recovery log data are identical.

According to an embodiment of the present invention, the database management server 1000 generates a plurality of adjacent log data groups, in which a plurality of sub log data groups are divided into a plurality of groups, Based, and segmented.

For example, if the recovery log data having the location information of the associated specific data block is divided into three parts as shown in FIG. 4 (500), the database management server 1000 determines that the three- Data can be grouped to create sublog data groups. In this case, the database management server 1000 may have created a sub log data group associated with a specific data block whose location information is " block address: 2 ".

When a sub log data group is generated as shown in (500) of FIG. 4, the database management server 1000 can compare a plurality of sub log data groups. In this case, the database management server 1000 may generate at least one neighbor log data group by comparing position information of a plurality of specific data blocks associated with the plurality of sub log data groups. The database management server 1000 determines whether the specific data blocks associated with the two sub log data groups are adjacent to each other in the persistent storage medium 3000 based on the location information (block address) , Adjacent log data groups can be created.

Here, when the adjacent log data group is created, the database management server 1000 can acquire the specific data blocks associated with the adjacent log data group from the permanent storage medium 3000 at one time. Then, the acquired specific data blocks are loaded into the storage unit 200, and the sub-log data associated with the specific data blocks are successively applied to perform database restoration. In this case, each of the sublog data may contain a history of changes to specific data blocks.

The number of times that the database management server 1000 acquires specific data blocks from the persistent storage medium 3000 is reduced by the database management server 1000 sorting and sorting the recovery log data by specific data blocks associated with the recovery log data .

FIG. 5 illustrates a method for asynchronously acquiring a plurality of adjacent data blocks by a database management server according to an embodiment of the present invention.

According to an embodiment of the present invention, the database management server 1000 may acquire specific data blocks associated with the adjacent log data group from the persistent storage medium 3000 asynchronously.

Here, the fact that the database management server 1000 acquires specific data blocks in an asynchronous manner means that before the permanent storage medium 3000 completes the data transfer to the database management server 1000, the database management server 1000 sends a data transfer request It is effective to reduce the database recovery time when the time required for the input / output process (requesting and acquiring data in the database recovery process) to the persistent storage medium 3000 is longer than the data processing time Lt; / RTI >

For example, when the transmitting / receiving unit 300 acquires the A data block and the B data block, after acquiring the A data block and completing the data recovery operation, The next data block can be obtained.

In accordance with an embodiment of the present invention, at least two specific data blocks are contiguous in the persistent storage medium 3000, meaning that the locations according to the block address information of at least two specific data blocks are stored in the persistent storage medium 3000 And may be close enough to acquire a block of data at a time.

For example, if the specific data block associated with the first sublog data group is "block address: 1" and the particular data block associated with the second sublog data group is "block address: 2", the database management server 1000 May determine the location of particular data blocks within the persistent storage medium 3000 based on the block address of the particular data blocks. If the specific data blocks can be acquired from the persistent storage medium in one attempt, the database management server 1000 can determine that the first sub log data group and the second sub log data group are adjacent. The database management server 1000 may generate the first neighbor log data group including the adjacent first sub log data group and the second sub log data group.

In the two adjacent log data groups 400 shown in FIG. 5, two sub log data groups of "block address: 1" and "block address: 2" are generated as the adjacent log data group, 3 "," block address: 4 ", and" block address: 5 "are generated as adjacent log data groups. Here, two data blocks associated with two sublog data groups, " block address: 1 ", " block address: 2 ", are acquired by the database management server 1000 from the persistent storage medium 3000 It can be acquired at once, not at the same time. The three data blocks associated with the three sublog data groups, "block address: 3", "block address: 4", "block address: 5" , But can be acquired at once.

According to an embodiment of the present invention, when the database management server 1000 acquires a plurality of data blocks to be recovered from the persistent storage medium 3000, it can acquire it in a predetermined unit and in an asynchronous manner.

Here, the predetermined unit may include the bandwidth of the persistent storage medium 3000, but the present invention is not limited thereto.

When the database management server 1000 acquires the data block to be recovered asynchronously, it can utilize the maximum bandwidth provided by the persistent storage medium 3000, thereby reducing the recovery time of the database.

Obtaining in an asynchronous manner is more efficient than data processing in the input / output process (requesting and acquiring data in the database recovery process) to the persistent storage medium 3000 in such a manner as to allow other processes to continue before the data transfer is completed If time is spent, it can be effective in reducing database recovery time.

For example, if the bandwidth of the persistent storage medium 3000 is equal to the size of two data blocks, the database management server 1000 determines whether the location information is "block address: 1", "block address: 3 ", " block address: 4 ", and " block address: 5 " are acquired from the persistent storage medium 3000 It can be acquired asynchronously to the bandwidth (size of two data blocks).

5 is one embodiment for explaining the present invention, and the manner in which the database management server 1000 of the present invention acquires specific data blocks is not limited to the above-described embodiment.

Those of ordinary skill in the art will understand that information and signals may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced in the above description may include voltages, currents, electromagnetic waves, magnetic fields or particles, Particles or particles, or any combination thereof.

Those skilled in the art will appreciate that the various illustrative logical blocks, modules, processors, means, circuits, and algorithm steps described in connection with the embodiments disclosed herein may be implemented or performed with a specific purpose, (Which may be referred to herein as "software") or a combination of both. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends on the design constraints imposed on the particular application and the overall system. Those skilled in the art may implement the described functions in various ways for each particular application, but such implementation decisions should not be interpreted as being outside the scope of the present disclosure.

The various embodiments presented herein may be implemented as a method, apparatus, or article of manufacture using standard programming and / or engineering techniques. The term "article of manufacture" includes a computer program, carrier, or media accessible from any computer-readable device. Where the medium may comprise a storage medium. For example, the computer-readable storage medium can be a magnetic storage device (e.g., a hard disk, a floppy disk, a magnetic strip, etc.), an optical disk (e.g., CD, DVD, But are not limited to, memory devices (e. G., EEPROM, card, stick, key drive, etc.). In addition, the various storage media presented herein include, but are not limited to, one or more devices and / or other machine-readable media for storing information.

It will be appreciated that the particular order or hierarchy of steps in the presented processes is an example of exemplary approaches. It will be appreciated that, based on design priorities, a particular order or hierarchy of steps in the processes may be rearranged within the scope of this disclosure. The appended method claims provide elements of the various steps in a sample order, but are not meant to be limited to the specific order or hierarchy presented.

The description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the disclosure. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the scope of the present disclosure. Thus, the present disclosure should not be construed as limited to the embodiments set forth herein, but is to be accorded the widest scope consistent with the principles and novel features presented herein.

Claims (1)

A computer program that can be stored on a computer readable storage medium.

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