JP2018136752A - Information processing system, information processing device and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce waiting time for access to a recording medium.SOLUTION: A storage unit 1a stores information on a combination of a recording medium M1 and a recording medium M2 that is a storage destination of synchronization data of data stored in the recording medium M1. A processing unit 1b, based on identification information for specifying an access path to a recording medium of a storage destination of data that an access is requested and combination information stored in the storage unit 1a, specifies the recording medium M1 and the recording medium M2 that are associated with the data storage destination among the plurality of recording media. The processing section 1b, when a usage status of the specified recording medium M1 is checked and the recording medium M1 is being accessed by using one of drives, instructs a library device 2 to access the identified recording medium M2 using other drive.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an information processing system, an information processing apparatus, and a program.

  Currently, library devices capable of storing a plurality of recording media are used. An example of the recording medium is a magnetic tape medium. The library device is connected to the information processing device, and enables the information processing device to access data stored in the recording medium.

  For example, there is a proposal of a system for managing data stored on a magnetic tape medium using a file system called LTFS (Linear Tape File System). In LTFS, data recorded on a magnetic tape medium can be handled in units of files.

There is also a proposal for a storage device that stores the same data in two recording media, so that even if one recording medium becomes unusable, operation can be continued with the remaining recording media.
When the system goes down, the contents of the primary system and secondary system are always kept the same by checking the input / output (I / O) request queue and matching the update contents of the primary system and secondary system. There is also a proposal for an information processing system.

JP, 2006-51294, A JP 2012-194867 A JP-A-11-282634

  A plurality of access requests may occur at the same time for one recording medium. In this case, for example, the library device performs access (previous access) according to the access request received earlier, and after the previous access is completed, the access according to the access request received later (later access) is performed. It is possible to do it. However, in this case, there is a problem that a waiting time is generated before the start of subsequent access.

  In one aspect, the present invention aims to reduce the latency of access to a recording medium.

  In one aspect, an information processing system is provided. The information processing system includes a library device and an information processing device. The library apparatus stores a plurality of recording media including a first recording medium and a second recording medium, includes a plurality of drives used for accessing each recording medium, and uses the plurality of drives. Data synchronization processing is performed between at least two of the plurality of recording media. The information processing apparatus includes: a first recording medium that is associated with a data storage destination among a plurality of recording media based on identification information that specifies an access path to the storage medium that stores the requested data. The second recording medium that is one of the storage destinations of the synchronization data of the data is identified, the usage status of the identified first recording medium is confirmed, and the first recording medium is connected to any drive. If the access is performed using the library device, the library apparatus is instructed to access the specified second recording medium using another drive.

  In one aspect, the waiting time for access to the recording medium can be reduced.

It is a figure which shows the information processing system of 1st Embodiment. It is a figure which shows the example of the information processing system of 2nd Embodiment. It is a figure which shows the hardware example of a server. It is a figure which shows the hardware example of a library. It is a figure which shows the example of file management by LTFS. It is a figure which shows the example of the partition of a tape medium. It is a figure which shows the function example of an information processing system. It is a figure which shows the example of medium management information. It is a flowchart which shows the example of access control. It is a flowchart which shows the example of access execution. It is a flowchart which shows the example of a synchronous process. It is a figure which shows the example of a sort of a copy order. It is a flowchart which shows the other example of access control.

Hereinafter, the present embodiment will be described with reference to the drawings.
[First Embodiment]
FIG. 1 illustrates an information processing system according to the first embodiment. The information processing system according to the first embodiment includes an information processing device 1 and a library device 2. The information processing apparatus 1 and the library apparatus 2 are connected using a predetermined cable. The information processing apparatus 1 and the library apparatus 2 may be connected via a network.

  The library apparatus 2 can store a plurality of recording media. The recording medium is, for example, a magnetic tape medium. The recording medium may be another type of recording medium such as an optical disk medium. The recording medium stores various data.

  The information processing device 1 accepts access requests from the terminal devices 3 and 4 for data stored in the library device 2. For example, the information processing device 1 and the terminal devices 3 and 4 are connected to the network 5. The terminal devices 3 and 4 transmit an access request to the information processing device 1 via the network 5.

  The information processing device 1 supports access by the terminal devices 3 and 4 to data stored in a plurality of recording media stored in the library device 2. For example, the information processing apparatus 1 may provide a file system function called LTFS so that the data stored in the recording medium is recognized as a file by the terminal apparatuses 3 and 4. The information processing apparatus 1 instructs the library apparatus 2 to execute access to the access target recording medium in response to the access request received from the terminal apparatuses 3 and 4. The information processing apparatus 1 acquires the execution result of access by the library apparatus 2 from the library apparatus 2. The information processing apparatus 1 responds to the terminal apparatuses 3 and 4 with the execution result acquired from the library apparatus 2.

Here, the information processing apparatus 1 provides a function for avoiding access competition with respect to a single recording medium. The information processing apparatus 1 includes a storage unit 1a and a processing unit 1b.
The storage unit 1a may be a volatile storage device such as a RAM (Random Access Memory) or a non-volatile storage device such as an HDD (Hard Disk Drive) or a flash memory. The processing unit 1b may include a CPU (Central Processing Unit), a DSP (Digital Signal Processor), an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), and the like. The processing unit 1b may be a processor that executes a program. As used herein, the “processor” may include a set of multiple processors (multiprocessor).

  The library apparatus 2 can be connected to the information processing apparatus 1 and includes a shelf 2a and drives 2b and 2c. The shelf 2a stores a plurality of recording media. The plurality of recording media includes recording media M1 and M2. The medium name (identifier) of the recording medium M1 is “LT001”. The medium name (identifier) of the recording medium M2 is “LT002”. The drives 2b and 2c are used for accessing each recording medium. Each of the drives 2b and 2c accommodates one recording medium, and accesses (reads and writes data) the accommodated recording medium. The library apparatus 2 has a robot (not shown in FIG. 1) that transports a recording medium inside the library apparatus 2. The library apparatus 2 transports the recording medium between the shelf 2a and the drives 2b and 2c using a robot.

  The library apparatus 2 uses the drives 2b and 2c to perform data synchronization processing between at least two of the plurality of recording media. For example, the library apparatus 2 stores a copy of data stored in the recording medium M1 (referred to as synchronization data) in the recording medium M2, thereby performing data synchronization processing between the recording media M1 and M2.

  The data stored in the recording media M1 and M2 may be a file. For example, the recording medium M1 stores a file “a.txt” and a file “b.txt” (the text format is an example, and a file of another format may be used). Similarly, the recording medium M2 stores the file “a.txt” and the file “b.txt”.

  The storage unit 1a stores information on a combination of the recording medium M1 and the recording medium M2 that stores synchronization data of data stored in the recording medium M1. Three or more recording media may belong to one combination. A combination of recording media can also be called a group of recording media.

  For example, if the name of the combination to which the recording media M1 and M2 belong (referred to as a group name) is “group1”, the group name “group1” may be considered as identification information of the combination. The medium name of the recording medium M1 is “LT001”, and the medium name of the recording medium M2 is “LT002”. In this case, the storage unit 1a also stores a correspondence relationship between the group name “group1” and the medium name pair “{LT001, LT002}”.

  As described above, it is conceivable that the information processing apparatus 1 provides LTFS. When using LTFS, the information processing device 1 provides the terminal devices 3 and 4 with symbolic links for designating a file stored in a specific recording medium (for example, the recording medium M1). The symbolic link indicates a directory corresponding to the medium name of any one recording medium belonging to the corresponding combination in terms of the function of the file system. The directory is represented by a predetermined access path (sometimes simply referred to as a path) including the corresponding medium name.

  For example, the storage unit 1a stores the correspondence relationship between the symbolic link “tmp” and the actual directory “/ xxx / LT001”. Then, the medium name “LT001” can be specified from the symbolic link “tmp”. When the medium name “LT001” is specified, “LT002” paired with the medium name “LT001” is changed based on the combination information “{LT001, LT002}” stored in the storage unit 1a. It can be specified. Therefore, in this case, the symbolic link “tmp” can be considered as identification information indirectly associated with the combination to which the recording media M1 and M2 belong. The designation destination of the symbolic link “tmp” may be different for each data (each file). For example, a link destination of “tmp” may be a path corresponding to “LT001” in a certain file, and a link destination of “tmp” may be a path corresponding to “LT002” in another file.

  The processing unit 1b uses the first recording medium associated with the data storage destination among the plurality of recording media based on the identification information that specifies the access path to the storage medium that stores the requested data. And the second recording medium that is one of the storage destinations of the synchronization data of the data is specified.

  As an example, the terminal device 4 inputs an access request corresponding to the command “vi / tmp / a.txt” to the information processing device 1 (the command “vi” is an example and may be another command). In this case, the access request includes designation of a path “/tmp/a.txt” corresponding to the file. As described above, “tmp” is a symbolic link and is identification information indicating the actual directory path “/ xxx / LT001”. The path “/ xxx / LT001” includes the medium name “LT001”.

  Therefore, the processing unit 1b can specify the recording medium M1 by the medium name included in the path corresponding to the symbolic link. Further, the processing unit 1b identifies the medium name “LT002” based on the information of the medium name combination “{LT001, LT002}” stored in the storage unit 1a. In this way, the processing unit 1b specifies the recording medium M2 that is paired with the recording medium M1.

  Then, the processing unit 1b confirms the usage status of the identified first recording medium. For example, the processing unit 1b confirms the usage status of the recording medium M1 from the history of the access instruction status for the library device 2. Alternatively, the processing unit 1b may check the usage status of the recording medium M1 by inquiring the usage status of the recording medium M1 to the library device 2.

  If the recording medium M1 is not currently used as a result of confirmation of the usage status of the recording medium M1, the processing unit 1b outputs an access instruction for the corresponding data stored in the recording medium M1 to the library device 2.

  On the other hand, in this example, it is assumed that the library apparatus 2 is executing access from the terminal apparatus 3 to the file “b.txt” stored in the recording medium M1 using the drive 2b. That is, the recording medium M1 is accessed using the drive 2b (the recording medium M1 is being used). In this case, the processing unit 1b instructs the library apparatus 2 to access the recording medium M2 using a drive other than the drive 2b (for example, the drive 2c). The processing unit 1b may specify a drive to be used for access to the library device 2 or may cause the library device 2 to select a free drive.

  Specifically, the processing unit 1b switches the access destination path by converting the part “LT001” corresponding to the medium name in the path “/ xxx / LT001” to the medium name “LT002” of the recording medium M2. . It can be said that this process is a process of switching the link destination by the symbolic link. That is, the processing unit 1b changes the path specifying the access destination file from “/tmp/a.txt” including the symbolic link to “/ xxx / LT002” via “/xxx/LT001/a.txt”. /A.txt ”.

  Then, the processing unit 1b outputs an access instruction corresponding to the converted path to the library device 2. For example, the access instruction includes information specifying the recording medium M2 as an access target, and information specifying an address range on the recording medium M2 in which a file corresponding to the path “/xxx/LT002/a.txt” is recorded. including. The processing unit 1b specifies the recording medium M2 corresponding to the converted path and the address range on the recording medium M2 based on predetermined index information (for example, stored in the storage unit 1a) used in LTFS. Also good. Alternatively, the processing unit 1b designates the converted path to the library apparatus 2, and the library apparatus 2 uses the library apparatus 2 to determine the address range on the recording medium M2 corresponding to the converted path based on the index information of the recording medium M2. It may be specified.

  The library apparatus 2 receives an access instruction from the processing unit 1b. For example, the library apparatus 2 recognizes that access to a predetermined address range of the recording medium M2 is requested by an access instruction. The library apparatus 2 conveys the recording medium M2 stored in the shelf 2a to the drive 2c by a robot. The library device 2 reads the data (file) in the corresponding address range in the recording medium M2 using the drive 2c, and provides it to the information processing device 1.

  The processing unit 1b acquires data read by the library device 2. Then, the processing unit 1b responds to the terminal device 4 with the read data. Thereafter, the processing unit 1b accepts an operation (for example, editing by an editor) on the corresponding data by the terminal device 4, and instructs the library device 2 to update data according to the operation, to end access to the data, or the like. .

When the access to the corresponding data is completed, the library apparatus 2 transports the recording medium M2 stored in the drive 2c by a robot and stores it in a predetermined position on the shelf 2a.
As a result of the above processing, the identity of the data stored in each of the recording media M1 and M2 is lost. Therefore, the processing unit 1b uses the library device 2 to synchronize the data stored in the recording medium M1 and the data stored in the recording medium M2 with the latest state at a predetermined timing. The identity of the data stored in each of the media M1 and M2 is restored.

  As described above, the information processing apparatus 1 selects the recording medium M2 as an access destination in accordance with the usage status of the recording medium M1. As a result, access contention for a single recording medium can be avoided, and the waiting time for access to the recording medium can be reduced.

  Here, in the above example, consider a case where the file “a.txt” and the file “b.txt” are stored only in the recording medium M1. In this case, if the recording medium M1 is being used by a previous access request designating the file “b.txt”, the library apparatus 2 may receive an access request after designating “a.txt”. Therefore, access according to a later access request cannot be performed immediately. That is, an access conflict occurs with respect to the recording medium M1, and a wait occurs for an access corresponding to a later access request.

  On the other hand, according to the information processing system of the first embodiment, the file “a.txt” and the file “b.txt” are stored in both the recording media M1 and M2. Therefore, even if the file “b.txt” on the recording medium M1 is being accessed using the drive 2b, the file “a.txt” on the recording medium M2 can be accessed using the drive 2c. That is, even when an access request for the file “a.txt” is received when the file “b.txt” is being accessed, it is not necessary to wait for an access according to the access request. In this way, by distributing access to a plurality of recording media, it is possible to avoid contention for access to a single recording medium, and to reduce the waiting time for access to the recording medium. As a result, the response delay of access to data can be reduced, and the speed of access to data can be increased.

  Further, as illustrated, by using a symbolic link mechanism for switching the access destination recording medium, the access destination can be switched at high speed by changing the link destination path. Further, it is not necessary for the terminal devices 3 and 4 to be aware of the recording medium to be accessed, and the influence on data utilization can be suppressed.

  After confirming that the recording medium M1 is being used, the processing unit 1b identifies the recording medium M2 that is paired with the recording medium M1, and instructs the library apparatus 2 to access the recording medium M2. Also good.

Hereinafter, as an example of the information processing apparatus 1, a server computer that provides LTFS will be described and the functions of the information processing apparatus 1 will be described in more detail.
[Second Embodiment]
FIG. 2 is a diagram illustrating an example of an information processing system according to the second embodiment. The information processing system according to the second embodiment includes a server 100 and a library 200. The server 100 and the library 200 are connected using a predetermined cable. The server 100 and the library 200 may be connected via a network such as a SAN (Storage Area Network). The server 100 is connected to the network 10. The network 10 is, for example, a LAN (Local Area Network). Clients 300 and 400 are connected to the network 10. The server 100 and the clients 300 and 400 can communicate via the network 10.

  The server 100 is a server computer that provides data used for business processing in the clients 300 and 400 to the clients 300 and 400. The server 100 functions as a file server and can handle data in file units.

  The library 200 is a device that can store a plurality of tape media. The library 200 may be called a library device. Here, the tape medium may be called a magnetic tape medium or a magnetic tape. An example of a tape medium standard is LTO (Linear Tape-Open, registered trademark). However, the tape medium may be of a standard other than LTO, such as DLT (Digital Linear Tape, registered trademark) and DDS (Digital Data Storage).

  The clients 300 and 400 are client computers used for user's work. Clients 300 and 400 access files stored on a tape medium stored in library 200 via server 100. The user can operate the clients 300 and 400 to check the contents of the file and update the contents of the file. For example, a user using the clients 300 and 400 may log in to the server 100 using a predetermined terminal emulator executed by the clients 300 and 400 and input a file operation command to the server 100. The clients 300 and 400 can also download a file stored on a tape medium via the server 100.

  Here, the server 100 has an LTFS function. The server 100 provides data stored in the tape medium stored in the library 200 to the clients 300 and 400 as a file by the function of the LTFS.

  LTFS is used, for example, for file archive operations. “Archive” means storing a file (for example, a moving image file, a medical image file, or accounting information) that requires a relatively large storage capacity to be stored for a relatively long period of time, although the access frequency is low. Specifically, a file with a high access frequency is stored in an HDD (on the server 100) or an SSD (Solid State Drive) that can be accessed at a higher speed than a tape medium. On the other hand, by archiving a file with low access frequency on a tape medium that is cheaper than HDD or SSD, a large amount of data can be stored at low cost. The access frequency of the archive target file is relatively low. Therefore, it may be considered that the archive target file is relatively unlikely to be updated again in a short time after being updated at a certain timing.

  FIG. 3 is a diagram illustrating a hardware example of the server. The server 100 includes a processor 101, a RAM 102, an HDD 103, a host bus adapter (HBA) 104, an image signal processing unit 105, an input signal processing unit 106, a medium reader 107, and a communication interface 108. Each hardware is connected to the server 100 bus.

  The processor 101 is hardware that controls information processing of the server 100. The processor 101 may be a multiprocessor. The processor 101 is, for example, a CPU, DSP, ASIC, or FPGA. The processor 101 may be a combination of two or more elements of CPU, DSP, ASIC, FPGA, and the like.

  The RAM 102 is a main storage device of the server 100. The RAM 102 temporarily stores at least part of an OS (Operating System) program and application programs to be executed by the processor 101. The RAM 102 stores various data used for processing by the processor 101.

  The HDD 103 is an auxiliary storage device of the server 100. The HDD 103 magnetically writes and reads data to and from the built-in magnetic disk. The HDD 103 stores an OS program, application programs, and various data. The server 100 may include other types of auxiliary storage devices such as a flash memory and an SSD, and may include a plurality of auxiliary storage devices.

  The HBA 104 is an interface connected to the library 200. As the HBA 104, for example, a Fiber Channel (FC) interface or SAS (Serial Attached SCSI, SCSI is an abbreviation for Small Computer System Interface) can be used.

  The image signal processing unit 105 outputs an image to the display 11 connected to the server 100 in accordance with an instruction from the processor 101. As the display 11, a CRT (Cathode Ray Tube) display, a liquid crystal display, or the like can be used.

  The input signal processing unit 106 acquires an input signal from the input device 12 connected to the server 100 and outputs it to the processor 101. As the input device 12, for example, a pointing device such as a mouse or a touch panel, a keyboard, or the like can be used.

  The medium reader 107 is a device that reads a program and data recorded on the recording medium 13. As the recording medium 13, for example, a magnetic disk such as a flexible disk (FD) or an HDD, an optical disk such as a CD (Compact Disc) or a DVD (Digital Versatile Disc), or a magneto-optical disk (MO) is used. Can be used. Further, as the recording medium 13, for example, a non-volatile semiconductor memory such as a flash memory card can be used. For example, the medium reader 107 stores a program or data read from the recording medium 13 in the RAM 102 or the HDD 103 in accordance with an instruction from the processor 101.

  The communication interface 108 communicates with other devices via the network 10. The communication interface 108 may be a wired communication interface or a wireless communication interface.

The clients 300 and 400 can also be realized using the same hardware as the server 100.
FIG. 4 is a diagram illustrating an example of hardware of a library. The library 200 includes a processor 201, a RAM 202, a flash memory 203, a connection interface 204, a shelf 205, a robot 206, and drives 207 and 208. Each hardware is connected to the library 200 bus.

  The processor 201 is hardware that controls information processing of the library 200. The processor 201 may be a multiprocessor. The processor 201 is, for example, a CPU, DSP, ASIC, or FPGA. The processor 201 may be a combination of two or more elements among CPU, DSP, ASIC, FPGA, and the like.

  The RAM 202 is a main storage device of the library 200. The RAM 202 temporarily stores at least part of firmware programs and application programs to be executed by the processor 201. The RAM 202 stores various data used for processing by the processor 201.

  The flash memory 203 is an auxiliary storage device for the library 200. The flash memory 203 electrically writes data to and reads data from a built-in storage element. The flash memory 203 stores a firmware program, application programs, and various data.

  The connection interface 204 is an interface that connects to the server 100. As the connection interface 204, for example, an FC or SAS interface can be used.

  The shelf 205 is a storage shelf that stores a plurality of tape media. The shelf 205 includes a plurality of cells. A cell is a storage space for storing one tape medium. An ID (IDentifier) is attached to the cell. The cell and the tape medium stored in the cell have a one-to-one correspondence, and the tape medium can be identified by the cell ID.

  Here, the tape medium has a magnetic tape and a cartridge that accommodates the magnetic tape. The magnetic tape is a tape-like film on which a magnetic material is deposited or applied. The cartridge is a case having a predetermined shape for housing the magnetic tape. For example, the cartridge is given the medium name of the tape medium (a label printed with a barcode may be attached to the cartridge, or an RFID (Radio Frequency IDentifier) tag in which the medium name is recorded is built into the cartridge. May be). The medium name of the tape medium is an identifier of the tape medium.

  For example, the shelf 205 stores tape media MT1, MT2, MT3, MT4,. As the tape media MT1, MT2, MT3, MT4,..., For example, those conforming to the LTO standard as described above can be used.

  The robot 206 conveys the tape medium stored in the shelf 205 to the drive 207 or the drive 208 in accordance with an instruction from the processor 201. Also, the robot 206 conveys the tape medium stored in the drive 207 or the drive 208 to the shelf 205 in accordance with an instruction from the processor 201. For example, the robot 206 recognizes the medium name of the tape medium by reading a barcode or an RFID tag attached to the tape medium cartridge.

  Drives 207 and 208 are tape drives for writing and reading data to and from the tape media MT1, MT2, MT3, MT4,... According to instructions from the processor 201. The drive 207 stores one tape medium, and can write and read data on the magnetic tape. Similarly, the drive 208 can store one tape medium and write and read data on the magnetic tape. Library 200 may have more than two drives.

  FIG. 5 is a diagram showing an example of file management by LTFS. For example, the server 100 executes the virtual file system 21, the FUSE (File system in Userspace) 22, and the device driver 23 using the OS kernel space (the address space of the RAM 102 in which the OS kernel exists).

  The virtual file system 21 provides the application 31 with a directory structure view for accessing files stored on the tape medium. The FUSE 22 is a software interface provided by the OS of the server 100, accepts an access request to the directory structure by the virtual file system 21, and provides the access request to other user software (for example, LTFS). It can be said that the virtual file system 21 is a first file system realized by the FUSE 22. The device driver 23 is driver software that controls the operation of the library 200.

  Further, the server 100 executes the business application 31 and the LTFS 32 using a user space (an address space of the RAM 102 in which user-oriented software exists).

  The application 31 issues an access request for the file according to the directory structure provided by the virtual file system 21. By issuing the access request, the application 31 can instruct file operations to the LTFS 32 via the virtual file system 21 and the FUSE 22. The LTFS 32 refers to the index information 33 held by the server 100 and identifies the name of the tape medium that holds the file and the address on the tape medium that stores the file. The LTFS 32 instructs the library 200 via the device driver 23 to convey the corresponding tape medium to a predetermined drive and write or read the corresponding file. The LTFS 32 can be said to be a second file system that manages the correspondence between the access path included in the access request and the identifier of the tape medium using the index information 33.

  Here, the file stored in the tape medium is designated by designating a predetermined path (for example, “/tmp/a.txt”). In this case, the “/ tmp” portion in the path is a symbolic link. A symbolic link is a logical link associated with an actual directory path. For example, the symbolic link “/ tmp” is associated with the directory path “/ LTO / (medium name)”. A predetermined medium name is inserted in the “(medium name)” portion. Therefore, in LTFS, the tape medium is accessed by converting the path “/tmp/a.txt” including the symbolic link into the path “/ LTO / (medium name) /a.txt”. In the index information 33, the address of the corresponding tape medium corresponding to the path “/ LTO / (medium name) /a.txt” is registered. The address is information indicating a physical recording position on the tape medium in which the file is recorded.

  FIG. 6 is a diagram illustrating an example of a partition of a tape medium. The storage area of the tape medium MT1 is divided into an index partition P1 and a data partition P2. The index partition P1 is an area for recording index information. The data partition P2 is an area for recording files.

  Here, the index information is information for identifying a file recorded in the data partition P2. The index information includes directory structure information and file attribute information in the data partition P2. The index information includes a file pointer indicating the recording position (address) of each file in the data partition P2.

  The tape media MT2, MT3, MT4,... Have an index partition and a data partition, similarly to the tape medium MT1. The server 100 acquires index information from the tape media MT1, MT2, MT3, MT4,... And stores them locally, and manages the files recorded on the tape media based on the index information.

FIG. 7 is a diagram illustrating an example of functions of the information processing system. The server 100 includes a storage unit 110, an access control unit 120, and a synchronization control unit 130.
The storage unit 110 is realized using a storage area of the RAM 102 or a storage area of the HDD 103. Further, the access control unit 120 and the synchronization control unit 130 are realized by the processor 101. Specifically, the processor 101 performs the functions of the access control unit 120 and the synchronization control unit 130 by executing a program stored in the RAM 102. However, the access control unit 120 and the synchronization control unit 130 may be realized by hard wired logic such as FPGA or ASIC.

  The storage unit 110 stores medium management information. The medium management information is information for managing the tape media MT1, MT2, MT3, MT4,. A predetermined number of tape media belong to one group. In the example of the second embodiment, the predetermined number is 2 (however, it may be 3 or more). In this case, one group can be called a pair of two tape media. Each tape medium belonging to a certain group stores the same set of files. That is, a set of files is stored redundantly by a plurality of tape media belonging to a certain group.

  In addition, the storage unit 110 stores index information read from each of the tape media MT1, MT2, MT3, MT4,. The index information stored in the server 100 and each tape medium is updated to the latest information by the access control unit 120 every time the file stored in each tape medium is updated.

  The access control unit 120 controls file access to the tape medium by LTFS. When the access control unit 120 acquires an access request for a file from the client 300, the access control unit 120 specifies a tape medium in which the file is stored. When the corresponding tape medium is not used for file access or the like, the access control unit 120 instructs the library 200 to access a file stored on the corresponding tape medium. In addition, when the corresponding tape medium is used for file access or the like, the access control unit 120 instructs the library 200 to access a file stored in another tape medium belonging to the same group as the corresponding tape medium. .

  The synchronization control unit 130 controls synchronization processing of files stored in two tape media belonging to a certain group. Here, the synchronization processing is processing for updating each file set stored in a plurality of tape media belonging to the same group to the latest state. As a result of the synchronization processing, the file set stored in the first tape medium belonging to a certain group and the file set stored in the second tape medium belonging to the group become the same, and each file is The constituent data is also the same. In other words, the updated contents of the file stored in the first tape medium are reflected in the file with the same name on the second tape medium by the synchronization process. In addition, the update contents of the file stored in the second tape medium are reflected in the file having the same name stored in the first tape medium.

  For example, the synchronization control unit 130 periodically outputs a synchronization processing execution instruction for each group to the library 200. At this time, the synchronization control unit 130 determines the order of copying each file from one tape medium to the other tape medium for a plurality of files to be synchronized (described later).

  The library 200 has an access execution unit 210. The access execution unit 210 is realized by the processor 201. Specifically, the processor 201 performs the function of the access execution unit 210 by executing a program stored in the RAM 202. However, the access execution unit 210 may be realized by hard wired logic such as FPGA or ASIC.

  The access execution unit 210 receives an instruction to access a file. The access execution unit 210 controls the robot 206 in response to an instruction to access the file, and conveys the instructed tape medium to the drive 207 or the drive 208. The access execution unit 210 reads the file stored in the corresponding tape medium using the drive 207 or the drive 208 and responds to the access control unit 120 with the read file.

  In addition, the access execution unit 210 receives an instruction to execute a synchronization process. The access execution unit 210 controls the robot 206 in accordance with the execution instruction of the synchronization process, and conveys the synchronization source tape medium belonging to the synchronization target group to the drive 207 or the drive 208. The access execution unit 210 uses the drive 207 or the drive 208 to read out the synchronization target file from the synchronization source tape medium and store it in the RAM 202. The access execution unit 210 controls the robot 206 to convey the synchronization target tape medium belonging to the synchronization target group to the drive 207 or the drive 208. The access execution unit 210 uses the drive 207 or the drive 208 to write the synchronization target file stored in the RAM 202 to the synchronization destination tape medium. The access execution unit 210 stores the synchronization source tape medium and the synchronization destination tape medium in the drive 207 and the drive 208, reads the synchronization target file from the synchronization source tape medium, and writes the synchronization target tape medium to the synchronization destination tape medium. The file to be synchronized may be written.

  FIG. 8 is a diagram illustrating an example of the medium management information. The medium management information is information used for update management of files included in a pair of tape media. The medium management information is created for each pair and stored in the storage unit 110. Here, it is assumed that the tape media MT1 and MT2 are managed as one pair. The medium management information 111 is an example of medium management information corresponding to a pair of tape media MT1 and MT2. Hereinafter, the information included in the medium management information 111 will be described using the line number assigned to the left side of the medium management information 111.

  The first line is an update flag. The update flag indicates whether any file in the pair has been updated after the previous synchronization. For example, the update flag “0” indicates that any file in the pair has not been updated after the previous synchronization. The update flag “1” indicates that any file in the pair has been updated after the previous synchronization.

  The second and third lines are media names (tape medium identification information) of tape media belonging to the pair. For example, “LTO1234L5” on the second line is the medium name of the tape medium MT1. Further, “LTO6789L5” in the third line is the medium name of the tape medium MT2.

The fourth line is a blank line.
The fifth and subsequent lines are a list of file names of files included in the pair. One file name is registered in one line. In addition, an update parameter is registered at the end of the file name of each line (following the colon symbol “:”).

  The update parameter is update information indicating on which tape medium of the pair the latest version of the corresponding file is stored. The update parameter “0” indicates that the corresponding file is not updated (that is, the latest version is stored on both tape media). The update parameter “1” indicates that the latest version of the corresponding file is stored in the tape medium MT1 corresponding to the medium name “LTO1234L5” on the second line. The update parameter “2” indicates that the latest version of the corresponding file is stored in the tape medium MT2 corresponding to the medium name “LTO6789L5” on the third line.

  For example, information “Text.txt: 1” is registered in the fifth line of the medium management information 111. This indicates that a file with the file name “Text.txt” is stored in both the tape media MT1 and MT2. It also indicates that the latest version of the file is stored in the tape medium MT1 (the file with the file name stored in the tape medium MT2 is not the latest version).

  Also, information “Picture.jpg: 0” is registered in the sixth line of the medium management information 111. This indicates that a file with the file name “Picture.jpg” is stored in both the tape media MT1 and MT2. It also indicates that the file has not been updated since the previous synchronization.

  In addition, information “PP.dat: 2” is registered in the seventh line of the medium management information 111. This indicates that a file with the file name “PP.dat” is stored in both the tape media MT1 and MT2. The latest version of the file is stored in the tape medium MT2 (the file with the file name stored in the tape medium MT1 is not the latest version).

The initial value of the update flag (the value immediately after the completion of synchronization) is “0”. The initial value of the update parameter corresponding to each file (the value immediately after the completion of synchronization) is “0”.
For other files included in the pair of tape media MT1 and MT2, the file name and the update parameter are registered in the medium management information 111.

  Next, an access control procedure for the tape medium by the server 100 will be described. Here, in the following description, a tape medium (for example, the tape medium MT1) directly associated with the symbolic link is referred to as a “primary medium” for convenience. Further, a tape medium (for example, the tape medium MT2) paired with the primary medium will be referred to as a “sub medium” for convenience. It can be said that the secondary medium is a tape medium that is indirectly associated with the symbolic link through the primary medium.

  FIG. 9 is a flowchart illustrating an example of access control. In the following, the process illustrated in FIG. 9 will be described in order of step number. The following procedure is executed when the server 100 receives an access request specifying an access destination file. As described above, the access destination file is designated by a predetermined path including a symbolic link.

  (S11) Upon receiving an access request from the client 300, the access control unit 120 checks a link destination by a symbolic link. Then, the access control unit 120 checks whether or not the link destination (the latest version storage destination) of the file specified in the access request is a primary medium.

  For example, the access request includes the path “/tmp/a.txt”. “/ Tmp” is a symbolic link and indicates an actual directory path “/ LTO / LT1234L5” or a path “/ LTO / LT5678L5” (which path is changed according to the update parameter of the medium management information 111). ). In this case, the link destination by the symbolic link is the tape medium MT1 corresponding to the medium name “LT1234L5” or the tape medium MT2 corresponding to the medium name “LT5678L5”.

  The access control unit 120 refers to the medium management information 111 stored in the storage unit 110, and the latest version of the corresponding file “a.txt” is stored in either the tape medium MT1 or the tape medium MT2. Check whether or not When the update parameter of the relevant file is “0” or “1”, it is assumed that the link destination (the latest version storage destination) corresponding to the file is the tape medium MT1. When the update parameter of the corresponding file is “2”, it is assumed that the link destination corresponding to the file is the tape medium MT2. In the description after step S12, the case where the link destination for the file specified in the access request in step S11 is a normal medium will be described. When the link destination for the file is a secondary medium, the access control unit 120 accesses the file stored in the secondary medium (the description of the procedure is omitted).

  (S12) The access control unit 120 determines whether the primary medium is normal. If the primary medium is normal, the access control unit 120 advances the processing to step S13. If the primary medium is not normal, the access control unit 120 advances the processing to step S14. Here, “the primary medium is normal” means that the file stored in the primary medium can be appropriately accessed. In addition, “primary medium is not normal” means that an abnormality (for example, damage to the cartridge of the tape medium or deterioration or contamination of the magnetic tape) has occurred in the primary medium, and the file stored on the primary medium Means that it cannot be accessed. For example, the access control unit 120 collects information about normal / abnormal detection results of each tape medium by the library 200 and records the information in the storage unit 110. The access control unit 120 determines whether or not the normal medium is normal by referring to the information on the normal / abnormal detection result of each tape medium stored in the storage unit 110.

  (S13) The access control unit 120 determines whether the corresponding primary medium is not used by another user. When the primary medium is not used by another user, the access control unit 120 advances the process to step S18. If the primary medium is being used by another user, the access control unit 120 advances the processing to step S15. Here, “when the primary medium is used by another user” is, for example, a case where the primary medium is currently used for file access by the client 400. That is, the primary medium is stored in any drive of the library 200, and access such as reading and writing of files is performed by the drive. On the other hand, “when the primary medium is not used by another user” is a case where the primary medium is not currently used for file access. It can be said that the determination in step S13 is a determination of the usage status of the primary medium.

  For example, the access control unit 120 determines whether or not the primary medium is being used by another user based on the history of access instructions for the library 200. The access instruction history may be recorded in the storage unit 110 in response to an access instruction to the library 200 by the access control unit 120. Further, the access control unit 120 inquires of the library 200 about the usage status of the primary medium, and makes the determination in step S13 based on the inquiry result of the usage status of the primary medium (result of being used or not being used). You may go.

  (S14) The access control unit 120 changes the link to a secondary medium. Specifically, the access control unit 120 changes the link destination path “/ LTO / LT1234L5” corresponding to the primary medium to the link destination path “/ LTO / LT6789L5” corresponding to the secondary medium based on the medium management information 111. Change to "". Since there is an abnormality in the primary medium, all the links to the primary medium are switched to links to the secondary medium until the abnormality of the primary medium is recovered. And the access control part 120 advances a process to step S20.

  (S15) The access control unit 120 determines whether or not the secondary medium is normal. If the secondary medium is normal, the access control unit 120 proceeds to step S16. If the secondary medium is not normal, the access control unit 120 advances the processing to step S17. Here, the access control unit 120 specifies a sub-medium for the primary medium based on the medium management information 111 stored in the storage unit 110. Further, the access control unit 120 can determine whether or not the secondary medium is normal in the same manner as in step S12.

  (S16) The access control unit 120 refers to the medium management information 111 and determines whether or not the update parameter corresponding to the file name of the file specified by the access request is “0”. If the update parameter corresponding to the file name of the corresponding file is “0”, the access control unit 120 advances the process to step S19. If the update parameter corresponding to the file name of the corresponding file is not “0” (that is, “1”), the access control unit 120 advances the process to step S17.

  (S17) The access control unit 120 waits until the access to the primary medium is completed. When the access to the primary medium is completed, the access control unit 120 advances the process to step S18.

  (S18) The access control unit 120 determines that the tape medium that is the access destination for the current access request is the primary medium, and instructs the library 200 to access the file on the primary medium. Details of the access processing to the primary medium will be described later. The access control unit 120 acquires the corresponding file from the library 200 and transmits it to the client 300. Then, the access control unit 120 ends the process.

  (S19) The access control unit 120 changes the link to a secondary medium. Specifically, the access control unit 120 changes the link destination path “/ LTO / LT1234L5” corresponding to the primary medium to the link destination path “/ LTO / LT6789L5” corresponding to the secondary medium based on the medium management information 111. Change to "".

  (S20) The access control unit 120 determines that the access destination tape medium for the current access request is the secondary medium, and instructs the library 200 to access the file on the secondary medium. Details of the processing for accessing the sub-media will be described later. The access control unit 120 acquires the corresponding file from the library 200 and transmits it to the client 300. Then, the access control unit 120 ends the process.

  FIG. 10 is a flowchart illustrating an access execution example. In the following, the process illustrated in FIG. 10 will be described in order of step number. The procedure shown below corresponds to step S18 and step S20 in FIG. 9 (the same procedure is accessed for both the primary medium and the secondary medium).

  (S21) The access control unit 120 updates the medium management information 111 in the storage unit 110. Specifically, the access control unit 120 updates the update flag of the medium management information 111 to “1” (when it is originally “1”, it is overwritten). Further, the access control unit 120 sets the update parameter corresponding to the file name of the file designated this time to a value corresponding to the tape medium of the access destination (“1” for the primary medium and “2” for the secondary medium). Update. Note that the access control unit 120 also saves and stores the medium management information 111 before update in a predetermined area of the storage unit 110.

(S22) The access control unit 120 instructs the library 200 to move the tape medium determined as the access destination (move from the shelf 205 to an empty drive).
(S23) The access control unit 120 instructs the library 200 to perform a file operation on the file according to the access request received from the client 300. For example, the file operation may include obtaining the contents of the file, updating the file, or ending the file access. Here, the file update indicates that the corresponding file is updated and the updated file is stored in the tape medium.

  (S24) When the file access to the corresponding file is completed, the access control unit 120 determines whether or not the file has been updated. If updated, the access control unit 120 ends the process. If not updated, the access control unit 120 proceeds to step S25.

  (S25) The access control unit 120 returns the update flag in the medium management information 111 to the value before the update in step S21. In addition, the access control unit 120 returns the update parameter of the corresponding file in the medium management information 111 to the value before the update in step S21. Then, the access control unit 120 ends the process.

  Here, Step S21 and Step S25 are processes for exclusive control with respect to the same file. For example, when the update parameter of the access target file in the medium management information 111 is set to “1” in step S21, if an access request for the file is received while the file is being accessed, No in step S16 of FIG. It is determined. As a result, two access requests for the tape medium MT1 can be prevented from being processed in parallel. For example, when the update parameter of the access target file in the medium management information 111 is set to “2” in step S21, two access requests for the same file on the tape medium MT2 are processed in parallel. Can be suppressed. This is because when the secondary medium is being accessed, the access control unit 120 waits until the previous access is completed before executing subsequent access to the secondary medium.

  In addition, there may be a case where a plurality of accesses to different files stored in the secondary medium occur at the same time. In this case, the access control unit 120 performs a plurality of accesses to the secondary medium in order (however, such a case is considered rare because the access frequency to the archive target file is low). . However, it is also possible to avoid such access contention for the sub-media by grouping three or more tape media and storing the same file set on the three or more tape media.

  As described with reference to FIGS. 9 and 10, the server 100 selects the tape medium MT2 as an access destination in accordance with the usage status of the tape medium MT1. More specifically, the server 100 converts a first path that includes a medium name of the tape medium MT1 corresponding to the symbolic link into a second path that includes the medium name of the tape medium MT2. Thus, the access destination for the file is switched from the tape medium MT1 to the tape medium MT2.

Thereby, access contention for a single tape medium can be avoided, and the waiting time for access to the tape medium can be reduced.
Now, consider a plurality of files included in a set of files recorded on a first tape medium and a second tape medium belonging to one pair. Among the plurality of files, the first tape medium is updated for the first file, and the second tape medium is updated for the second file when the synchronization process is performed. There is. In this case, for the first file, the first tape medium is the synchronization source and the second tape medium is the synchronization destination. On the other hand, for the second file, the second tape medium is the synchronization source, and the first tape medium is the synchronization destination. That is, the synchronization source tape medium and the synchronization destination tape medium are switched for each file.

  In addition, the writing of a file to the tape medium is an additional writing method. Specifically, the updated file is added to the end of the used area of all storage areas on the tape medium, and the file pointer of the corresponding file is changed to indicate the area where the updated file is added. Is done. The storage area corresponding to the file before update is managed as, for example, a reusable area or an invalid area.

Therefore, the synchronization control unit 130 provides a synchronization control function in consideration of such a writing method for the tape medium.
FIG. 11 is a flowchart illustrating an example of synchronization processing. In the following, the process illustrated in FIG. 11 will be described in order of step number. The following procedure is periodically executed by the synchronization control unit 130 at a predetermined cycle.

  (S31) The synchronization control unit 130 refers to the medium management information 111 stored in the storage unit 110 and identifies a pair of tape media to be synchronized. Specifically, when the update flag of the medium management information 111 is “1”, the synchronization control unit 130 sets the tape media MT1 and MT2 as a pair of synchronization target tape media. On the other hand, when the update flag of the medium management information 111 is “0”, the synchronization control unit 130 does not set the tape media MT1 and MT2 as a pair of tape media to be synchronized. The synchronization control unit 130 executes the procedure from step S32 on the pair of tape media to be synchronized.

  (S32) The synchronization control unit 130 identifies an updated file from the file set stored in the pair identified in step S31. Specifically, in the medium management information 111, the synchronization control unit 130 replaces a file whose update parameter corresponding to the file name is other than “0” (that is, “1” or “2”) with an updated file (update Specified file). The updated file (updated file) is the latest version of the file stored in the pair, and can be said to be synchronization target data.

  (S33) The synchronization control unit 130 sorts the copy order of the updated files. Specifically, the synchronization control unit 130 first determines the copy order so that the updated file is copied from the primary medium to the secondary medium, and then copies the updated file from the secondary medium to the primary medium. Next, the copy order is determined. However, the synchronization control unit 130 may determine the copy order so that copying from the secondary medium to the primary medium is performed first, and copying from the primary medium to the secondary medium is performed later.

(S34) The synchronization control unit 130 instructs the library 200 to execute the copy of the updated file in the sorted order.
(S35) The synchronization control unit 130 resets the update flag of the synchronized pair. Specifically, when the synchronization processing for the tape media MT1 and MT2 is completed, the synchronization control unit 130 sets the update flag “1” (updated) in the medium management information 111 to “0” (not updated). . Further, the synchronization control unit 130 sets all the update parameters of each file in the medium management information 111 to “0”.

  As described above, the server 100 stores the update parameter (update information) indicating the file update of the tape media MT1 and MT2, and is stored in the tape media MT1 and MT2 based on the update parameter. The library 200 is instructed to synchronize each data set (file set).

  At this time, the server 100 stores all the synchronization target files stored in the tape medium MT1 in the tape medium MT2 and then stores the synchronization target files stored in the tape medium MT2 in the tape medium MT1. Control synchronization.

FIG. 12 is a diagram illustrating an example of sorting in copy order. For example, a set of a file name and an update parameter is registered in each line of the medium management information 111.
Specifically, the update parameter for the file name “A” is “1”. The update parameter for the file name “B” is “2”. The update parameter for the file name “C” is “0”. The update parameter for the file name “D” is “1”. The update parameter for the file name “E” is “1”. The update parameter for the file name “F” is “2”. The update parameter for the file name “G” is “0”. The update parameter for the file name “H” is “1”.

  The medium management information 111a represents a list of file names after sorting by the synchronization control unit 130. Specifically, in the medium management information 111a, file names “A”, “D”, “E”, and “H” of the updated files stored in the primary medium are arranged first. Next, the file names “B” and “F” of the updated files stored in the secondary medium are arranged. Files “C” and “G” that have not been updated are arranged last. Files “C” and “G” that have not been updated are not subject to copying (that is, not subject to synchronization processing).

  The synchronization control unit 130 copies the updated file from the primary medium to the secondary medium and from the secondary medium to the primary medium in the order indicated by the medium management information 111a (the order from the upper side to the lower side in the figure). 200 is instructed.

  In response to an instruction from the synchronization control unit 130, the access execution unit 210 first stores the updated file read from the primary medium in the secondary medium. As described above, the access execution unit 210 appends the updated file of the primary medium to the end of the used area of the secondary medium. When the appending of all the updated files on the primary medium is completed, the access execution unit 210 stores the updated file read from the secondary medium in the primary medium. The access execution unit 210 appends the updated file of the secondary medium to the end of the used area of the primary medium.

  Here, for example, it is conceivable that the synchronization processing is performed in the order from the upper side to the lower side of the list of file names in the medium management information 111 without sorting in the copy order. However, in this case, there is a possibility that the library 200 switches the synchronization source / synchronization destination tape medium a plurality of times. In addition, an updated file to be written to the synchronization destination and an updated file read from the synchronization source can be alternately written to one tape medium. However, if the file is read and written alternately to the tape medium a plurality of times, there is a possibility that the time for the synchronization process becomes longer. This is because the seek operation of the file position with respect to the tape medium occurs frequently.

  Therefore, as described above, the synchronization control unit 130 sorts the copy order in advance, so that the library 200 can switch the synchronization source / destination tape medium only once. Further, the target file can be continuously added to the synchronization destination tape medium. For this reason, the number of seek operations for the file position on the tape medium can be suppressed, and the synchronization processing can be speeded up.

  In addition, when one tape medium of a pair becomes unusable, the synchronization control unit 130 replaces the unusable tape medium with a new tape medium, and recreates the pair. Specifically, the synchronization control unit 130 updates the medium management information 111 with the medium name of the new tape medium (updates the old medium name with the new medium name). Then, the synchronization control unit 130 performs high-speed recovery by storing the file set of the existing tape medium in the pair also in the new tape medium by the above-described synchronization processing. During pair recovery, the recovery target pair is temporarily operated on one tape medium.

In addition, the access control unit 120 may perform access control in consideration of the synchronization processing performed by the synchronization control unit 130. Specifically, it is as follows.
FIG. 13 is a flowchart illustrating another example of access control. In the following, the process illustrated in FIG. 13 will be described in order of step number. The following procedure is executed when the server 100 receives an access request specifying an access destination file.

  (S41) The access control unit 120 determines whether or not the synchronization control unit 130 is performing synchronization processing. When the synchronization process is being performed, the access control unit 120 advances the process to step S43. If the synchronization process is not being performed, the access control unit 120 advances the process to step S42.

  (S42) The access control unit 120 performs normal access processing. The procedure of the normal access process corresponds to the procedure illustrated in FIG. Then, the access control unit 120 ends the process.

  (S43) The access control unit 120 determines whether or not the tape medium to be accessed (access target medium) is a tape medium being synchronized. If the access target medium is a tape medium being synchronized, the access control unit 120 advances the process to step S45. If the access target medium is not a tape medium being synchronized, the access control unit 120 advances the process to step S44.

  (S44) The access control unit 120 determines whether there is an empty drive in the library 200. If there is an empty drive, the access control unit 120 advances the process to step S48. If there is no free drive, the access control unit 120 advances the process to step S45.

  (S45) The access control unit 120 instructs the synchronization control unit 130 to interrupt the synchronization process. The synchronization control unit 130 interrupts the synchronization process according to the instruction to interrupt the synchronization process, and records the progress information of the synchronization process in the storage unit 110. The progress information of the synchronization process is information indicating the interruption position of the synchronization process for the corresponding pair (the file at which the synchronization is interrupted and the address at the time of interruption of the synchronization destination tape medium). If the access target medium is not a pair for which the synchronization processing has been interrupted, the library 200 can take out the tape medium for which the synchronization processing has been interrupted from the drive (drive 207 or drive 208) (even in the case of No in step S44) Can be prepared).

(S46) The access control unit 120 performs normal access processing. The procedure of the normal access process corresponds to the procedure illustrated in FIG.
(S47) When the normal access process in step S46 is completed, the access control unit 120 instructs the synchronization control unit 130 to resume the synchronization process from the interruption position. The synchronization control unit 130 resumes the synchronization process from the interruption position based on the progress information of the synchronization process stored in the storage unit 110. Then, the access control unit 120 ends the process.

  (S48) The access control unit 120 performs a normal access process using an empty drive in the library 200. The procedure of the normal access process corresponds to the procedure illustrated in FIG. Then, the access control unit 120 ends the process.

  As described above, when the server 100 receives an access request for a file stored in the synchronized tape medium while synchronization is being performed, the server 100 interrupts synchronization by the library 200 and performs access according to the access request to the library. 200 is instructed.

  That is, even during the synchronization process, the access control unit 120 performs control so that the file access to the access request by the clients 300 and 400 is executed with priority over the synchronization process. The synchronization control unit 130 saves the copy status of the file when the synchronization process is interrupted in the storage unit 110, and resumes the synchronization process after the file access is completed. Similarly, in the case of the pair recovery process, the synchronization control unit 130 performs control so that the file access to the access request by the clients 300 and 400 is executed with priority over the recovery process.

In this way, even when synchronization processing and recovery processing are performed, the waiting time for access to the recording medium can be reduced without waiting until the synchronization processing or recovery processing is completed.
In addition, even when a drive is being used by synchronization processing or recovery processing and there is no free drive, the waiting time for access to the recording medium is reduced by preparing the free drive by interrupting the synchronization processing or recovery processing. be able to.

  As described above, according to the server 100, the accessibility of files by the clients 300 and 400 can be improved in the archive operation of the library 200 by the LTFS. In addition, the continuity of operation can be improved by providing a high-speed recovery function when a medium error occurs. When using these functions, a user who operates using a file does not need to be aware of the synchronization processing by the server 100, and can access the file even during synchronization or file recovery. Become.

  Further, by utilizing a symbolic link mechanism for switching the tape medium of the access destination, the access destination can be switched at high speed by changing the link destination path. Further, the client 300 or 400 does not need to be aware of the tape medium to be accessed, and the influence on the file usage by the user can be suppressed.

  Then, by operating the two tape media as a pair, when the tape medium to be accessed is used by another user, the paired tape media can be used. For this reason, the access waiting time is omitted, and the file can be accessed at high speed. Further, the synchronization processing performed periodically not only maintains consistency between tape media, but also functions as a backup, and can be used for file recovery in the event of a failure. During the synchronization process, a file access environment can be provided without making the user aware of the synchronization process. For this reason, the server 100 and the library 200 do not need to determine the execution time of the synchronization process in consideration of the possibility of access to the file by the user, and the synchronization process can be performed in the free time of the server 100 and the library 200. As a result, the server 100 and the library 200 can be efficiently operated.

  In the second embodiment, the tape medium is exemplified as the recording medium, but other types of media may be used. For example, the recording medium may be an optical disk medium such as Blu-ray (registered trademark). The library 200 may be a device that can store a plurality of optical disk media.

  The information processing according to the first embodiment can be realized by causing the processing unit 1b to execute a program. The information processing according to the second embodiment can be realized by causing the processor 101 to execute a program. The program can be recorded on a computer-readable recording medium 13.

  For example, the program can be distributed by distributing the recording medium 13 on which the program is recorded. Alternatively, the program may be stored in another computer and distributed via a network. For example, the computer stores (installs) a program recorded in the recording medium 13 or a program received from another computer in a storage device such as the RAM 102 or the HDD 103, and reads and executes the program from the storage device. Good.

DESCRIPTION OF SYMBOLS 1 Information processing apparatus 1a Memory | storage part 1b Processing part 2 Library apparatus 2a Shelf 2b, 2c Drive 3, 4 Terminal apparatus 5 Network M1, M2 Recording medium

Claims (10)

A plurality of recording media including a first recording medium and a second recording medium are accommodated, and a plurality of drives used for accessing each recording medium are provided. A library device that performs data synchronization processing between at least two of the recording media;
The first recording medium associated with the data storage destination among the plurality of recording media, based on identification information designating an access path to the storage medium of the storage destination of the requested data; The second recording medium that is one of the storage destinations of the synchronization data of the data is specified, the usage status of the specified first recording medium is confirmed, and the first recording medium is any drive An information processing device for instructing the library device to access the identified second recording medium using another drive;
An information processing system.   The information processing system according to claim 1, wherein the identification information is a symbolic link corresponding to a directory where the data is stored.   The information processing apparatus converts a first path that is a path of a directory corresponding to the symbolic link and includes an identifier of the first recording medium into a second path that includes an identifier of the second recording medium. The information processing system according to claim 2, wherein the access destination for the data is switched from the first recording medium to the second recording medium.   The information processing apparatus stores update information indicating which of the first recording medium and the second recording medium has been updated, and the first recording medium is based on the update information. 4. The information processing system according to claim 1, wherein the library apparatus is instructed to perform the synchronization processing using a medium and the second recording medium. 5.   When the information processing apparatus accepts the access request for the data while performing the synchronization process, the information processing apparatus interrupts the synchronization process by the library apparatus and instructs the library apparatus to access in accordance with the access request. The information processing system according to claim 4.   The information processing apparatus stores all the first synchronization target data stored in the first recording medium in the second recording medium, and then stores the second synchronization data stored in the second recording medium. 6. The information processing system according to claim 4, wherein the synchronization processing by the library device is controlled so that target data is stored in the first recording medium.   The information processing apparatus includes: a first file system that acquires the access request issued by a predetermined application; a correspondence between the access path included in the acquired access request and an identifier of the first recording medium A second file system that manages the relationship, and the second file system identifies the first recording medium by converting the access path into an identifier of the first recording medium. The information processing system according to any one of claims 1 to 6.   The information processing apparatus includes a storage unit that stores information on a combination of recording media including the first recording medium and the second recording medium that are targets of the synchronization processing, and 2. When the first recording medium is specified, the second recording medium belonging to the same combination as the first recording medium is specified with reference to the combination information stored in the storage unit. The information processing system according to any one of 1 to 7. An information processing apparatus having a plurality of drives used for accessing a recording medium and connectable to a library apparatus that stores the plurality of recording media,
A storage unit that stores information on a combination of a first recording medium and a second recording medium that is a storage destination of synchronization data of data stored in the first recording medium;
Based on identification information designating an access path to the storage medium of the storage destination of the data requested to be accessed and the combination information stored in the storage unit, the storage destination of the data among the plurality of recording media The first recording medium and the second recording medium that are associated with each other are identified, the usage status of the identified first recording medium is confirmed, and the first recording medium is connected to any drive. A processing unit for instructing the library apparatus to access the identified second recording medium using another drive,
An information processing apparatus. A computer that has a plurality of drives used for accessing a recording medium and that can be connected to a library apparatus that stores the plurality of recording media.
A first recording medium associated with the data storage destination among the plurality of recording media based on identification information designating an access path to the storage medium of the storage destination of the requested data; and Specify the second recording medium that is one of the storage destinations of the synchronization data of the data,
The usage status of the identified first recording medium is confirmed, and when the first recording medium is accessed using any drive, another drive for the identified second recording medium is selected. Instructing the library device to use access,
A program that executes processing.

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