JP6912105B2 - Disk array system, control method of disk array system, and disk array device - Google Patents

Description

The embodiments described below relate, for example, to a disk array system, a control method for the disk array system, and a disk array device.

In general, in a computer system containing multiple sites, it is possible to copy the data on the main site to a remote site. When the processing load on the data to the main site is high, it is possible to use a remote site to distribute the load. Alternatively, if some trouble occurs at the main site, the data at the remote site may be used to continue the business.

For example, in Patent Document 1, disclosure such as continuing business at a secondary site when a disaster occurs at the primary site can be seen (paragraph 0002, etc.). Further, according to Patent Document 1, a disk array may be used (paragraph 0026, etc.).

Japanese Unexamined Patent Publication No. 2010-170485 Japanese Unexamined Patent Publication No. 2012-022645 Japanese Unexamined Patent Publication No. 2012-003621

The following is an example. Therefore, the following does not limit the scope of the present invention.

In general, when update data occurs in a computer system having a plurality of sites, it is desirable that the update data is reflected without contradiction. For example, when the update data D1, D2, and D3 occur in this order in chronological order, it is preferable that the update data D1, D2, and D3 are reflected in this order.

Generally, for example, in a computer system including a plurality of sites, when copying data from a main site to a remote site, it is preferable to copy the updated data D1, D2, and D3 in this order if the above example is followed. For example, when there are a plurality of update data for the same area on the disk, an error may occur in the data if the update data is not copied in the order.

Therefore, one of the objects of the present invention may be to reflect the updated data without contradiction when the updated data is generated in the computer system having a plurality of sites. However, this point does not limit the scope of the present invention.

The following description is an example and does not limit the scope of the present invention.

In the embodiments described below, for example, a disk array system is disclosed. This disk array system may include, for example, a first disk array device and a second disk array device. The first disk array device has a first cache and a first I / O processing unit that receives update data from the outside, generates a cache ID corresponding to the update data, and writes the update data to the first cache. , The first order guarantee control unit that links the cache IDs in the order in which the update data is received and generates the link by the cache IDs may be provided. At a predetermined timing, the first order guarantee control unit may transmit the update data and the link by the cache ID to the second disk array device. The second disk array device receives the update data and the link by the cache ID from the second cache and the first disk array device, and refers to the link by the cache ID to receive the update data according to the order in which the update data is received. The second I / O processing unit that writes to the second cache and the update data stored in the second cache at a predetermined timing are written to the disk in the order of receiving the update data by referring to the link by the cache ID. The order guarantee control unit of 2 may be provided.

In the embodiments described below, for example, a control method for a disk array system is disclosed. The control method of this disk array system is, for example, a method of controlling a disk array system in a disk array system including a first disk array device and a second disk array device, and the first disk array device is a control method of the disk array system. A step of receiving update data from the outside, a step of the first disk array device generating a cache ID corresponding to the update data, and a step of writing the update data to the first cache, and a step of the first disk array device performing a cache ID. To generate a link by cache ID by linking in the order in which update data is received, and a step in which the first disk array device transmits the update data and the link by cache ID to the second disk array device. A step in which the second disk array device receives the update data and the link by the cache ID from the first disk array device, refers to the link by the cache ID, and writes the update data to the second cache according to the order in which the update data is received. , The second disk array device includes a step of writing the update data stored in the second cache at a predetermined timing to the disk according to the order of receiving the update data by referring to the link by the cache ID. May be good.

In the embodiments described below, for example, a first disk array device is disclosed. This first disk array device receives, for example, a first cache and update data from the outside, generates a cache ID corresponding to the update data, and writes the update data to the first cache. The processing unit and the first order guarantee control unit that links the cache IDs in the order in which the update data is received to generate the link by the cache ID are provided, and the first order guarantee control unit is provided at a predetermined timing. However, it may be the first disk array device that sends the update data and the link by the cache ID to the second disk array device to request the storage of the update data.

According to the embodiment described later, for example, when update data is generated in a computer system having a plurality of sites, the update data can be reflected without contradiction. For example, if update data D1, D2, and D3 occur in this order in chronological order, update data D1, D2, and D3 can be reflected in this order. However, this does not limit the scope of the present invention.

It is a drawing which shows the structure of the disk array system in embodiment of this application. It is a drawing which shows the process flow of the disk array system in this embodiment of this application. It is a drawing which shows the link by the cache ID in embodiment of this application. It is a drawing which shows the link by the cache ID in embodiment of this application. It is a drawing which shows the structure of the disk array apparatus in embodiment of this application. It is a drawing which shows the process flow of the disk array apparatus in embodiment of this application.

Hereinafter, some embodiments will be described with reference to the drawings. The following disclosure is an example. The scope of the present invention should not be construed as confined to the following disclosures.

1st Embodiment FIG. 1 is a drawing which shows the structure of the disk array system in 1st Embodiment. The configuration of the disk array system in this embodiment will be described with reference to FIG.

In FIG. 1, the disk array system in this embodiment includes a main site 1 and a remote site 2. The main site 1 and the remote site 2 are connected by a remote line 30, and data can be transmitted and received to and from each other. For example, the main site 1 transmits data to the remote site 2, and the remote site 2 receives and stores the data from the main site 1. That is, the data of the main site 1 can be copied to the remote site 2.

The remote line 30 is a network that connects the main site 1 and the remote site 2.

The main site 1 includes a data update host 10 and a disk array device 17. The data update host 10 and the disk array device 17 are independent devices, and may be connected via a network. Alternatively, the data update host 10 and the disk array device 17 may be the same device.

The disk array device 17 includes an I / O processing unit 11, a cache 12, a disk 16, and a disk control unit 15. Further, the disk array device 17 may have a storage unit (not shown) such as a memory.

The data update host 10 sends update data and a write request including information on the write destination. The update data may be, for example, data input to the data update host 10 by the user. Alternatively, the update data may be data received by the data update host 10 from an external device or medium. The writing destination information may be, for example, information indicating any disk included in the disk 16 and a writing position or address in the disk as the writing destination of the update data.

The I / O processing unit 11 inputs (or receives) the update data and the write destination information from the data update host 10. The I / O processing unit 11 outputs the update data to the cache 12. The cache 12 is a storage means for temporarily storing update data.

The disk 16 is a storage means for storing update data. The disc 16 may be a single disc. The disc 16 may be composed of a plurality of discs. Alternatively, the disk 16 may be a hard disk, an SSD (solid state drive), or the like. The update data may include data for updating the data already stored on the disk 16. The update data may include data newly added to the disk 16.

The disk control unit 15 is a means for writing data to the disk 16. The disk control unit 15 can check, for example, at regular intervals (for example, 5 seconds, 60 seconds, 300 seconds) whether or not there is updated data in the cache 12 that has not been written to the disk 16. .. When there is update data in the cache 12 that has not been written to the disk 16, the disk control unit 15 reads the update data that has not been written from the cache 12 and writes the read update data to the disk 16. It may be.

The order guarantee control unit 14 is a means for guaranteeing the order of the update data on the cache 12. The transmission unit 13 is a means for transmitting data to the remote site 2.

The remote site 2 receives and stores data from, for example, the main site 1. The remote site 2 includes a disk array device 27. The disk array device 17 and the disk array device 27 are connected via a remote line 30. The disk array device 27 includes a receiving unit 23, a cache 22, an I / O processing unit 21, an order guarantee control unit 24, a disk 26, and a disk control unit 25. Further, the disk array device 27 may have a storage unit (not shown) such as a memory.

The receiving unit 23 receives and outputs data from the main site 1 via the remote line 30. The I / O processing unit 21 inputs the data output by the receiving unit 23. The I / O processing unit 21 stores the input data in the cache 22. The disk control unit 25 writes the data stored in the cache 22 to the disk 26. The order guarantee control unit 24 guarantees the writing order of the data written to the disk 26.

FIG. 2 is a drawing showing a processing flow of the disk array system according to the present embodiment. The processing flow of the disk array system will be described with reference to FIG. Here, an example is shown in which the data update host 10 transmits three update data to the disk array device 17.

First, the data update host 10 sends update data D1. The I / O processing unit 11 of the disk array device 17 receives the update data D1 from the data update host 10 (circled number 1 in FIG. 2).

When transmitting the update data D1, the data update host 10 may send a write request including information on the write destination regarding the area on the disk 16 that stores the update data D1. The writing destination information may be, for example, a file path or a file name. Alternatively, the write destination information may be a SCSI (small computer system interface, SCSI) command or the like. The I / O processing unit 11 can receive the update data D1 and the write request.

The I / O processing unit 11 stores the update data D1 in the cache 12 (circled number 1 in FIG. 2). Further, the I / O processing unit 11 generates a cache ID corresponding to the update data D1. Here, the cache ID corresponding to the update data D1 is set to D1 so that it can be easily understood. The cache ID may be calculated, for example, from the information of the write destination of the update data D1 by a hash operation or the like. Further, the cache ID may include the storage position or address of the update data D1 in the cache 12. Alternatively, the cache ID may include a combination of a storage position or address of the update data D1 in the cache 12 and a random number. The I / O processing unit 11 may calculate the storage position or address of the update data D1 in the cache 12 by a hash operation. Further, the I / O processing unit 11 may calculate the storage position or address of the update data D1 in the cache 12 by a plurality of hash operations to avoid a collision. Alternatively, the storage position of the update data D1 in the cache 12 may be randomly assigned using a random number, and the cache ID and the storage position in the cache 12 may be determined as not necessarily related to each other.

The I / O processing unit 11 can refer to the writing destination information and determine the disk and address for storing the update data D1. The disk or address for storing the update data D1 is stored in the storage unit in association with the cache ID (and, if necessary, the storage position of the update data D1 in the cache 12), and can be referred to in the subsequent processing. The I / O processing unit 11 can also store the write destination information in the storage unit in association with the cache ID.

The I / O processing unit 11 outputs the cache ID (D1) to the order guarantee control unit 14. The order guarantee control unit 14 inputs the cache ID (D1). FIG. 3 shows a link by cache ID. The order guarantee control unit 14 inputs the cache ID from the I / O processing unit 11 and creates a link with the cache ID as shown by the circled number 1 in FIG. 3 (circled number 2 in FIG. 2). In the circled number 1 in FIG. 3, the link by the cache ID includes three elements 100, 200, and 300. Element 100 contains the cache ID (D1). Since element 200 and element 300 are generated and added in the subsequent processing, only element 100 exists at this stage. Element 100 (and element 200 and element 300) are created on the storage unit and are linked in the order in which the update data is input. This example is an example of a one-way link, but it may be in various forms such as a two-way link. The link by the cache ID may be stored in the storage unit, for example. Element 100 may have information indicating the next link destination. The information indicating the next link destination may be 0 (representing the end of the link) at this stage. The information indicating the next link destination may be updated to, for example, the address on the storage unit of the element 200 when the subsequent update data is added. Similarly, the same applies to the element 200 and the element 300 in FIG. 3, and at the end, the information indicating the next link destination may be a predetermined value indicating the end of the link such as 0.

When the cache ID is input from the I / O processing unit 11, the order guarantee control unit 14 may store the state information indicating the state of the update data corresponding to the cache ID in the storage unit. For example, when the cache ID (D1) is input from the I / O processing unit 11, the order guarantee control unit 14 sets "not transmitted" as the state of the update data (update data D1) corresponding to the cache ID (D1). The state information to be represented may be stored in the storage unit in association with the cache ID (D1). "Not sent" means that the corresponding update data has not been sent to the remote site 2. For the state information indicating "not transmitted", for example, a 2-byte area may be provided in advance in the element 100, and a predetermined value, for example, 0 may be set in this area. Alternatively, the state information may be stored in a table created in the storage unit separately from the link by the cache ID (element 100, etc.).

Further, the I / O processing unit 11 outputs the cache ID (D1) to the order guarantee control unit 14, and then transmits a response signal to the data update host 10. The response signal may indicate, for example, that the update data D1 has been successfully stored in the cache 12 (for example, 0), or that it has failed due to insufficient space in the cache 12 (for example). , -1). The response signal may, for example, simply indicate that the update data D1 has been received (for example, 1). The data update host 10 receives a response signal from the I / O processing unit 11. The data update host 10 may perform processing according to the response signal. For example, the data update host 10 may display a message such as data storage success on a display unit (not shown). For example, the data update host 10 may try to store the update data D1 again.

Continuing from the above, assume that the data update host 10 transmits update data D2 (circled number 3 in FIG. 2). The process until the I / O processing unit 11 outputs the cache ID to the order guarantee control unit 14 is the same as described above. Let D2 be the cache ID corresponding to the update data D2.

The I / O processing unit 11 outputs the cache ID (D2) to the order guarantee control unit 14. The order guarantee control unit 14 inputs the cache ID (D2). The order guarantee control unit 14 updates the link by the cache ID as shown by the circled number 1 in FIG. 3 (circled number 4 in FIG. 2). In the circled number 1 in FIG. 3, the link by the cache ID includes three elements 100, 200, and 300. Element 200 contains the cache ID (D2). Element 300 does not exist because it is created and added in subsequent processing, and elements 100 and 200 are present at this stage. Element 100 and element 200 (and element 300) are created on the storage unit and are linked in the order of input of update data. This example is an example of a one-way link, but it may be in various forms such as a two-way link. The link by the cache ID may be stored in the storage unit, for example. Element 100 (, 200, and 300) may have information indicating the next link destination. The information indicating the next link destination can be the address of element 200. The information indicating the next link destination in the element 200 may be 0, for example, indicating the end at this stage. When the subsequent update data (D3) is added, for example, the information indicating the next link destination in the element 200 may be updated to the address on the storage unit of the element 300.

The order guarantee control unit 14 stores the state information indicating "not transmitted" as the state of the update data (update data D2) corresponding to the cache ID (D2) in the storage unit in association with the cache ID (D2). May be good.

Further, the I / O processing unit 11 outputs the cache ID (D2) to the order guarantee control unit 14, and then transmits a response signal to the data update host 10. This process is the same as the above process for update data D1.

Continuing from the above, assume that the data update host 10 transmits update data D3 (circled number 5 in FIG. 2). The process until the I / O processing unit 11 outputs the cache ID to the order guarantee control unit 14 is the same as described above. Let D3 be the cache ID corresponding to the update data D3.

The order guarantee control unit 14 inputs the cache ID (D3). The order guarantee control unit 14 updates the link by the cache ID as shown by the circled number 1 in FIG. 3 (circled number 7 in FIG. 2). In the circled number 1 in FIG. 3, the link by cache ID includes three elements 100, 200, and 300. Element 300 contains the cache ID (D3). Element 100, element 200, and element 300 are created on the storage unit and are linked in the order in which update data is input. This example is an example of a one-way link, but it may be in various forms such as a two-way link. Element 200 may have information indicating the next link destination. The information indicating the next link destination can be the address of element 300. The information indicating the next link destination in the element 300 may be 0, for example, indicating the end at this stage. When subsequent update data is added, the information indicating the next link destination in the element 300 may be updated to, for example, an address on the storage unit of another element.

The order guarantee control unit 14 stores the state information indicating "not transmitted" as the state of the update data (update data D3) corresponding to the cache ID (D3) in the storage unit in association with the cache ID (D3). May be good.

Further, the I / O processing unit 11 outputs the cache ID (D3) to the order guarantee control unit 14, and then transmits a response signal to the data update host 10. This process is the same as the above process for update data D1.

The I / O processing unit 11 may check the size of the free area of the cache 12 before or after storing the update data in the cache 12, and further, the I / O processing unit 11 may check the size of the free area of the cache 12. When the size of the free area is smaller than a predetermined threshold value, a data transmission request may be output to the order guarantee control unit 14. This threshold may be, for example, 20% of the total capacity of cache 12. Alternatively, the I / O processing unit 11 may output a data transmission request to the order guarantee control unit 14 when a predetermined time has elapsed after storing the update data in the cache 12. This predetermined time may be, for example, 10 seconds.

The order guarantee control unit 14 inputs a data transmission request from the I / O processing unit 11 and reads out the update data stored in the cache 12. The order guarantee control unit 14 outputs the update data and the link by the cache ID stored in the storage unit (circled number 1 in FIG. 3) to the transmitting unit 13 (circled number 8 in FIG. 2).

Here, for example, the order guarantee control unit 14 connects the update data D1 to D3 in the order of update data D1, update data D2, and update data D3 with reference to the link by the cache ID of the circled number 1 in FIG. A set of data may be generated and output to the transmission unit 13. Further, the order guarantee control unit 14 may output the link by the cache ID to the transmission unit 13 so as to maintain the order of D1, D2, and D3. For example, the order guarantee control unit 14 may connect the element 100, the element 200, and the element 300 in this order to generate a set of data and output it to the transmission unit 13 (circled number 8 in FIG. 2). ). The transmission unit 13 inputs a set of update data data and a set of link data by cache ID from the order guarantee control unit 14, and transmits them to the remote site 2 via the remote line 30. Request storage (circled number 9 in Figure 2).

Alternatively, the order guarantee control unit 14 transmits, for example, update data D1 to D3 in the order of update data D1, update data D2, and update data D3 with reference to the link by the cache ID of the circled number 1 in FIG. It may be output to 13. Further, the order guarantee control unit 14 may output the link by the cache ID to the transmission unit 13 while maintaining the order of D1, D2, and D3. For example, the order guarantee control unit 14 may output the element 100, the element 200, and the element 300 to the transmission unit 13 in this order (circled number 8 in FIG. 2). The transmission unit 13 inputs the update data and the link by the cache ID from the order guarantee control unit 14, and transmits them to the remote site 2 via the remote line 30 in the input order (FIG. 2). Circled numbers 9). The order guarantee control unit 14 can read the storage destination information corresponding to the update data D1 to D3 from the storage unit, and can also transmit these to the remote site 2 via the transmission unit 13.

The receiving unit 23 of the remote site 2 is a set of data generated by connecting the transmitting unit 13 of the main site 1 in the order of update data D1, update data D2, and update data D3, as well as element 100, element 200, and element. A set of data generated by connecting in the order of 300 and storage destination information corresponding to the update data D1 to D3 may be received. The receiving unit 23 outputs them to the I / O processing unit 21.

Alternatively, the receiver 23 of the remote site 2 receives the update data in the order of update data D1, update data D2, and update data D3, and links by cache ID to element 100, element 200, and element 300. The storage destination information corresponding to the update data D1 to D3 may be received in order. The receiving unit 23 outputs them to the I / O processing unit 21.

The I / O processing unit 21 inputs the data output by the receiving unit 23. When the I / O processing unit 21 inputs a set of data generated by connecting the update data D1, the update data D2, and the update data D3 in this order, the update data D1, the update data D2, and the update data D3 are ordered in that order. Restore while maintaining. When the I / O processing unit 21 inputs a set of data generated by connecting the element 100, the element 200, and the element 300 in this order, the I / O processing unit 21 maintains the order of the element 100, the element 200, and the element 300. Restore while doing. The I / O processing unit 21 puts the restored update data D1, update data D2, update data D3, element 100, element 200, and element 300 on a storage unit such as a memory (not shown) of the remote site 2. Can hold. The I / O processing unit 21 stores the update data D1, the update data D2, and the update data D3 on the storage unit in the cache 22. The I / O processing unit 21 may include the storage positions of the update data D1, the update data D2, and the update data D3 in the cache 22 in the corresponding elements 100, 200, and 300. The I / O processing unit 21 outputs the element 100, the element 200, and the element 300 to the order guarantee control unit 24 while maintaining these orders (circled number 9 in FIG. 2). The I / O processing unit 21 stores the storage destination information corresponding to the update data D1 to D3 in the storage unit.

The order guarantee control unit 24 inputs elements 100, 200, and 300 from the I / O processing unit 21 while maintaining these orders (circled number 9 in FIG. 2). The order guarantee control unit 24 restores the link relationship between the element 100, the element 200, and the element 300. Element 100 may have information indicating the next link destination. The information indicating the next link destination can be, for example, an address on the storage unit of the element 200. Element 200 may have information indicating the next link destination. The information indicating the next link destination may be, for example, the address of the element 300 on the storage unit. Element 300 may have information indicating the next link destination. The information indicating the next link destination of the element 300 can be a predetermined value representing the end of the link, for example, 0.

When the elements 100 to 300 are input from the I / O processing unit 21, the order guarantee control unit 24 may store the state information indicating the state of the update data corresponding to them in the storage unit. For example, when the element 100 is input from the I / O processing unit 11, the order guarantee control unit 24 stores the state information indicating "received" as the state of the update data (update data D1) corresponding to the element 100. It may be stored in a unit. This state information can be, for example, information in a state in which the “untransmitted” part in the circled number 1 in FIG. 3 is replaced with “received”. "Received" indicates that the reception of the corresponding update data from the main site 1 has been completed. For the state information indicating "received", for example, a 2-byte area may be provided in advance in the element 100, and a predetermined value, for example 1, may be stored in this area. Alternatively, the state information may be stored in a table created in the storage unit separately from the link by the cache ID.

The order guarantee control unit 24 outputs a storage completion notification to the I / O processing unit 21. The I / O processing unit 21 inputs a storage completion notification from the order guarantee control unit 24. The I / O processing unit 21 transmits a storage completion notification to the receiving unit 23. The receiving unit 23 receives the storage completion notification from the I / O processing unit 21. The receiving unit 23 transmits a completion response to the transmitting unit 13 of the main site 1 (circled number 11 in FIG. 2).

The transmission unit 13 receives the completion response from the reception unit 23 of the remote site 2. The transmission unit 13 outputs the transmitted data information to the order guarantee control unit 14. The transmitted data information may be, for example, elements 100 to 300 transmitted by the transmission unit 13 to the remote site 2, or cache IDs (D1 to D3) which are a part thereof.

The order guarantee control unit 14 inputs the transmitted data information from the transmission unit 13 (circled number 12 in FIG. 2). The order guarantee control unit 14 refers to the transmitted data information and finds out the elements 100 to 300 in the storage unit. The order guarantee control unit 14 changes the state information of the elements 100 to 300 in the storage unit to “transmitted”. The circled number 2 in Figure 3 represents this update process, where the state information for elements 100 and 200 has already been changed to "sent" and the state information for element 300 is now changed to "sent". By the way (or, it may represent a state in which only update data D1 and update data D2 are transmitted to the remote site 2 and update data D3 is not transmitted).

By the above process, it may be clear which update data was sent to the remote site 2. In addition, it may be possible to suppress an error in the transmission process such as transmitting the same update data twice. Also, the updated data may be sent to the remote site in the order in which they were entered. Therefore, it is possible to prevent the update data transmission order from being changed. Therefore, it is possible to prevent the occurrence of inconsistency in updated data at the remote site.

The I / O processing unit 21 may check the size of the free area of the cache 22 before or after storing the update data in the cache 22, and further, the I / O processing unit 11 may check the size of the free area of the cache 22. When the size of the free area is smaller than a predetermined threshold value, a data write request may be output to the order guarantee control unit 24. This threshold may be, for example, 20% of the total capacity of the cache 22. The order guarantee control unit 24 inputs a data write request from the I / O processing unit 11, refers to the link by the cache ID in the storage unit and the status information, and caches the status information that is "received". The update data stored in 22 is read through the I / O processing unit 11 according to the order of linking by the cache ID. The order guarantee control unit 24 outputs update data to the disk control unit 25 according to the order of linking by the cache ID, and also outputs a write request to the disk 26 including the cache ID. The disk control unit 25 inputs a write request and update data from the order guarantee control unit 24, reads the storage destination corresponding to the cache ID by referring to the storage unit, and writes the update data to the disk 26 based on the storage destination. (Or, if applicable, overwrite the existing data with updated data). When the writing is successful, the disk control unit 25 outputs a write success response to the order guarantee control unit 24. The order guarantee control unit 24 inputs a write success response, and removes, releases, or indicates that the element in the link by the cache ID corresponding to the update data that was successfully written is an empty element, for example, " Write the information "free" to the status information. The order guarantee control unit 24 releases the area in the cache 22 of the update data that was successfully written via the I / O processing unit 11. Further, the order guarantee control unit 24 refers to the link by the cache ID in the storage unit, and the update data (for example, the status information is “received”) that has not been written to the disk 26 exists in the cache 22. If so, read further according to the order of links by cache ID. After that, when the update data (for example, the status information is "received") that has not been written to the disk 26 exists in the cache 22, the above-mentioned writing process to the disk 26 is repeated.

Further, the disk control unit 25 may output a data check request to the order guarantee control unit 24 at predetermined time intervals. This predetermined time may be, for example, 10 seconds. The sequence guarantee control unit 24 inputs a data check request from the disk control unit 25, refers to the link by the cache ID in the storage unit and the status information, and displays the status information "received" in the cache 22. The stored update data is read through the I / O processing unit 11 according to the order of linking by the cache ID. The order guarantee control unit 24 outputs update data to the disk control unit 25 according to the order of linking by the cache ID, and also outputs a write request to the disk 26 including the cache ID. The disk control unit 25 inputs a write request and update data from the order guarantee control unit 24, reads the storage destination corresponding to the cache ID by referring to the storage unit, and writes the update data to the disk 26 based on the storage destination. (Or, if applicable, overwrite the existing data with updated data). When the writing is successful, the disk control unit 25 outputs a write success response to the order guarantee control unit 24. The order guarantee control unit 24 inputs a write success response, and removes, releases, or indicates that the element in the link by the cache ID corresponding to the update data that was successfully written is an empty element, for example, " Write the information "free" to the status information. The order guarantee control unit 24 releases the area in the cache 22 of the update data that was successfully written via the I / O processing unit 11. Further, the order guarantee control unit 24 refers to the link by the cache ID in the storage unit, and the update data (for example, the status information is “received”) that has not been written to the disk 26 exists in the cache 22. If so, read further according to the order of links by cache ID. After that, when the update data (for example, the status information is "received") that has not been written to the disk 26 exists in the cache 22, the above-mentioned writing process to the disk 26 is repeated.

The update data of the cache 12 may be stored in the disk 16 also in the main site 1. For example, the disk control unit 15 may output a data check request to the order guarantee control unit 14 at predetermined time intervals. This predetermined time may be, for example, 10 seconds. The order guarantee control unit 14 inputs a data check request from the disk control unit 15, refers to the link and the state information by the cache ID in the storage unit, and the state information is "sent" in the cache 12, that is, Check if there is updated data that has been sent to remote site 2 and has not yet been written to disk 16. When the sequence guarantee control unit 14 determines that there is update data in the cache 12 that has been transmitted to the remote site 2 and has not yet been written to the disk 16 (for example, the status information is "". "Sent") refers to the link and status information by the cache ID in the storage unit, and reads the update data stored in the cache 12 via the I / O processing unit 11 in the order of the link by the cache ID. .. The order guarantee control unit 24 outputs the update data to the disk control unit 15 according to the order of linking by the cache ID, and also makes a write request requesting writing to the disk 16 including the update data and the corresponding cache ID. Output. The disk control unit 15 inputs a write request and update data from the order guarantee control unit 14, refers to the write destination information corresponding to the cache ID from the storage unit, and updates data to the disk 16 based on the write destination information. (Or, if applicable, overwrite existing data with updated data). When the writing is successful, the disk control unit 15 outputs a write success notification to the order guarantee control unit 14. The order guarantee control unit 14 inputs a write success notification, and removes, releases, or indicates that the element in the link by the cache ID corresponding to the update data that was successfully written is an empty element, for example, " Write the information "free" to the status information. In the circled number 3 in FIG. 3, the state information corresponding to the element D1 is blank, indicating that the writing of the update data D1 to the disk 16 is completed, that is, the state is “free”. .. The order guarantee control unit 14 may release the area in the cache 12 of the update data that has been successfully written through the I / O processing unit 11. Further, the order guarantee control unit 14 refers to the link by the cache ID in the storage unit, and the update data (for example, the status information is “sent”) that has not been written to the disk 16 exists in the cache 12. If so, read further according to the order of links by cache ID. After that, when the update data (for example, the status information is "sent") that has not been written to the disk 16 exists in the cache 12, the above-mentioned writing process to the disk 16 is repeated.

As described above, in the present embodiment, the update data is written to the disks of the main site 1 and the remote site 2 in the order of receiving the update data. Therefore, the writing order of the updated data is maintained, the writing order of the data does not change, and the data contradiction can be avoided.

Further, in the above embodiment, it is not necessary to provide a buffer between the I / O processing unit 11 (21) and the cache 12 (22). Therefore, it is not necessary to perform copy processing between the cache 12 (22) and the buffer. Therefore, the processing load at the main site 1 and the remote site 2 can be reduced. Therefore, at the main site 1, for example, many resources such as a processor can be used for communication and data exchange with the host 10. That is, according to the above embodiment, the performance of the main site 1 and the remote site 2 can be improved.

Further, as described above, since the main site 1 and the remote site 2 do not secure a dedicated buffer in the internal storage unit, for example, the vacant portion of the storage unit can be used for other purposes. For example, at the main site 1 and the remote site 2, other application programs may use the vacant part of the storage unit. Alternatively, since the storage unit has a margin at the main site 1 and the remote site 2, other application programs can be executed more stably.

Second Embodiment Next, the second embodiment will be described with reference to FIGS. 1 and 4. This embodiment may be used in addition to the above embodiment. In this embodiment, the components of FIG. 1 are similar to those described above. In this embodiment, as an example, it is assumed that the host 10 transmits update data D1, update data D2, update data D3, and update data D2'in this order, and the main site 1 receives them in the same order. Further, in this embodiment, it is assumed that the update data D2 and the update data D2'are both written to the same area of the disk 16.

Similar to the above embodiment, the I / O processing unit 11 stores the update data D1, the update data D2, the update data D3, and the update data D2'in the cache 12 in this order. In this process, since the update data D2 and the update data D2'are the update data related to the same area, the update data D2'is stored in the cache 12 and the update data D1 to D3 are transmitted to the remote site 2 (and). It may be after the writing to the disk 16 is completed. In this case, it may be necessary to wait for the update data D2'to be stored in the cache 12 until the transmission of the update data D2 to the remote site 2 (and writing to the disk 16) is completed. Therefore, in consideration of this, for example, the update data D2'may be allowed to be stored in the cache 12 even before the update data D2 is transmitted to the remote site 2 (and written to the disk 16). .. This process will be described below.

Similar to the above-described embodiment, the data update host 10 transmits update data D1 and a write request including information on the write destination. The I / O processing unit 11 of the disk array device 17 receives the update data D1 and the write request from the data update host 10 (circled number 1 in FIG. 2).

When the I / O processing unit 11 stores the update data D1 in the cache 12 (circled number 1 in FIG. 2), the I / O processing unit 11 refers to the write destination information and stores other update data in the same area as the update data D1. Check if is already in cache 12. At this stage, there is no other update data stored in the same area as the update data D1 in the cache 12. If there is no update data to be written to the same area as the update data D1 in the cache 12, the I / O processing unit 11 stores the update data D1 in the cache 12 and caches the write destination information in the storage unit. It is stored in association with the ID (D1), and the cache ID (D1) corresponding to the update data D1 is generated. The processing when the update data for writing to the same area as the update data D1 exists in the cache 12 corresponds to the case of the update data D2'described later.

The I / O processing unit 11 outputs the cache ID (D1) to the order guarantee control unit 14. The processing of the order guarantee control unit 14 is the same as described above. Further, the I / O processing unit 11 transmits a response signal to the data update host 10.

When the cache ID is input from the I / O processing unit 11, the sequence guarantee control unit 14 creates / updates the link by the cache ID as described above, and also represents the attribute of the update data corresponding to the cache ID. Attribute information may be stored in the storage unit. For example, when the cache ID (D1) is input from the I / O processing unit 11, the order guarantee control unit 14 represents “main” as an attribute of the update data (update data D1) corresponding to the cache ID (D1). Attribute information may be stored in the storage unit. “Main” indicates that it is the last update data written in the same area as the corresponding update data.

The data update host 10 sends update data D2 and a write request including information on the write destination (circled number 3 in FIG. 2). The I / O processing unit 11 of the disk array device 17 receives the update data D2 and the write request from the data update host 10.

The I / O processing unit 11 refers to the write destination information and confirms whether or not other update data to be stored in the same location as the update data D2 already exists in the cache 12. The information of the write destination of the update data D1 existing in the storage unit exists. The I / O processing unit 11 refers to the information of the write destinations of the update data D1 and D2, and confirms whether or not other update data to be stored in the same location as the update data D2 already exists in the cache 12. If there is no update data to be written to the same location as the update data D2 in the cache 12, the I / O processing unit 11 stores the update data D2 in the cache 12 and stores the update data D2 in the storage unit as described above. The information of the write destination of the update data D2 is stored in association with the cache ID (D2), and the cache ID (D2) corresponding to the update data D2 is generated. The processing when the update data to be written to the same location as the update data D2 exists in the cache 12 corresponds to the case of the update data D2'described later.

The I / O processing unit 11 outputs the cache ID (D2) to the order guarantee control unit 14. The processing of the order guarantee control unit 14 is the same as described above. Further, the I / O processing unit 11 transmits a response signal to the data update host 10. The response signal may be, for example, the same as described above. The data update host 10 receives a response signal from the I / O processing unit 11. The data update host 10 may perform processing according to the response signal.

When the cache ID is input from the I / O processing unit 11, the sequence guarantee control unit 14 creates / updates the link by the cache ID as described above, and also represents the attribute of the update data corresponding to the cache ID. Attribute information may be stored in the storage unit. For example, when the cache ID (D2) is input from the I / O processing unit 11, the order guarantee control unit 14 represents “main” as an attribute of the update data (update data D1) corresponding to the cache ID (D2). Attribute information may be stored in the storage unit.

The data update host 10 sends update data D3 and a write request including information on the write destination (circled number 5 in FIG. 2). The I / O processing unit 11 of the disk array device 17 receives the update data D3 and the write request from the data update host 10.

The I / O processing unit 11 refers to the information of the write destinations of the update data D2 and D3 in the storage unit, and confirms whether or not other update data to be stored in the same area as the update data D3 already exists in the cache 12. do. When there is no update data to be written to the same area as the update data D3 in the cache 12, the I / O processing unit 11 stores the update data D3 in the cache 12 and stores the update data D3 in the storage unit as described above. The information of the write destination of the update data D3 is stored in association with the cache ID (D3), and the cache ID (D3) corresponding to the update data D3 is generated. The processing when the update data to be written to the same location as the update data D3 exists in the cache 12 corresponds to the case of the update data D2'described later.

The I / O processing unit 11 outputs the cache ID (D3) to the order guarantee control unit 14. Further, the I / O processing unit 11 transmits a response signal to the data update host 10. The response signal may be, for example, the same as described above. The data update host 10 receives a response signal from the I / O processing unit 11. The data update host 10 may perform processing according to the response signal.

When the cache ID is input from the I / O processing unit 11, the sequence guarantee control unit 14 creates / updates the link by the cache ID as described above, and also represents the attribute of the update data corresponding to the cache ID. Attribute information may be stored in the storage unit. For example, when the cache ID (D3) is input from the I / O processing unit 11, the order guarantee control unit 14 represents “main” as an attribute of the update data (update data D3) corresponding to the cache ID (D3). Attribute information may be stored in the storage unit.

The data update host 10 transmits update data D2'and a write request including information on the write destination. The I / O processing unit 11 of the disk array device 17 receives the update data D2'and the write request from the data update host 10.

The I / O processing unit 11 refers to the information of the write destinations of the update data D1, D2, and D3 in the storage unit, and whether or not other update data to be stored in the same area as the update data D3 already exists in the cache 12. To confirm. If there is no update data to be written to the same area as the update data D2'in the cache 12, the I / O processing unit 11 stores the information of the write destination of the update data D2' in the storage unit as described above. Is stored in association with the cache ID (D2'), and the cache ID (D3) corresponding to the update data D3 is generated.

Even if there is update data (D2) in the cache 12 that writes to the same location as the update data D2', the I / O processing unit 11 expels the update data (D2) from the cache 12. It does not wait until the update data D2'is stored in the cache 12. The I / O processing unit 11 stores the update data D2'in the cache 12. At this time, the I / O processing unit 11 may allocate, for example, an area for duplicate update data in the cache 12 in advance, and store the update data D2'in the area for duplicate update data. The I / O processing unit 11 generates a cache ID corresponding to the update data D2'. Here, the cache ID corresponding to the update data D2'is D2'.

The I / O processing unit 11 reads the cache ID (D2) of the update data D2 stored in the same area as the update data D2'from the storage unit. The I / O processing unit 11 outputs the cache ID (D2') and the cache ID (D2) to the order guarantee control unit 14. Further, the I / O processing unit 11 transmits a response signal to the data update host 10. The response signal may be, for example, the same as described above. The data update host 10 receives a response signal from the I / O processing unit 11. The data update host 10 may perform processing according to the response signal.

FIG. 4 shows a link by cache ID. The order guarantee control unit 14 inputs the cache ID (D2') and the cache ID (D2) from the I / O processing unit 11, and updates the same area on the disk with respect to the cache ID (D2). It is determined that the data corresponding to the cache ID (D2') has been accepted. The order guarantee control unit 14 creates / updates a link with a cache ID as shown by the circled number 1 in FIG. As shown by the circled number 1 in FIG. 4, the link by the cache ID includes three elements 100, 200, and 300. The order guarantee control unit 14 adds the element 400. The order guarantee control unit 14 links the most recently generated element 400 to the element 300 cache ID (D3), that is, the element 300 is linked to the element 400.

The order guarantee control unit 14 adds the element 400 corresponding to the cache ID (D2') to the link by the cache ID as shown by the circled number 2 in FIG. Further, the order guarantee control unit 14 may change, for example, the attribute information representing the attribute of the update data corresponding to the cache ID (D2) to "sub". “Sub” means that there is update data written in the same area as the corresponding update data. Regarding the cache ID (D2'), the attribute information may be stored in the storage unit with the attribute as "main".

The attribute information may be stored in a table created in the storage unit separately from the link by the cache ID.

In the state of the circled number 2 in FIG. 4, when the update data is transmitted to the remote site 2, the main site 1 may transmit the update data including the update data D2 and D2'to the remote site 2. That is, all updated data can be sent to the remote site 2 while maintaining the order. At this time, the attribute information can also be transmitted to the remote site 2. As a result, the remote site 2 can write the update data to the disk 26 while maintaining the order. At the remote site 2, regardless of whether the attribute information corresponding to the update data is "main" or "sub", the update data can be written to the disk 26 while maintaining the order. Alternatively, at the remote site 2, only those whose attribute information corresponding to the update data is "main" may be written to the disk 26 while maintaining the order of the update data. Similarly, writing to disk 16 at main site 1 can be performed while maintaining the order of the updated data.

As described above, in the present embodiment, the update data D2'is written to the cache 12 without waiting for the update data D2 to be transmitted (excluded) to the remote site 2. Therefore, the processing of the main site 1 can be high speed. Further, since it is not necessary to wait for the update data D2 to be transmitted (expulsed) to the remote site 2 at the main site 1 and write the update data D2'to the cache 12, for example, an update such as a buffer. The component for temporarily storing the data D2'can be omitted.

Here, in the present embodiment, for example, in the state of the circled number 2 in FIG. 4, when a data read request is transmitted from the outside such as the host 10 to the disk array device 17, and the read request is made. It is assumed that the data in the area of the update data D2'shown by the circled number 2 in FIG. 4 is requested to be read. In this case, the I / O processing unit 11 follows the link by the cache ID (via the order guarantee control unit 14), and the attribute information is "main" without referring to the update data D2 whose attribute information is "sub". The update data D2'is read from the cache 12. By such processing, the disk array device 17 can provide the latest state data.

Further, when the update data D2 ″ written to the same area as the update data D2 ′ is received by the disk array device 17 after the update data D2 ′ shown in the circled number 2 in FIG. 4 is stored in the cache 12. The attribute information of the update data D2'may be changed to "sub", and the attribute information of the update data D2 "may be stored in the cache 12 as the" main ". As a result, even if a plurality of update data for the same area is received, all of them can be stored in the cache.

As described above, in the present embodiment, even if update data to the same area occurs, the update data can be connected using one link to guarantee the update order. As a result, it is possible to prevent the update order from being incorrect.

Further, in the above embodiment, it may be omitted to use a dedicated buffer for writing to the cache. In this regard, for example, by preparing a dedicated buffer for copying between disk array devices, the update data received from the host at the main site is buffered, and the update data is stored in the buffer in order. There may be a method of guaranteeing and further reducing the communication overhead by sending the buffered data together to the remote site. Here, as the performance of the host / disk array is improved, a large buffer may be required due to factors such as writing a large amount of data or a temporary increase in load, but in this case, a large amount of internal resources are consumed. As a result, the buffer may be exhausted, and even if there is free space in the cache, the next update data may not be accepted. Further, when a dedicated buffer is prepared for copying between disk array devices, the internal load of the device may increase due to the copy process between the cache and the dedicated buffer. When it is possible to omit using a dedicated buffer for writing to the cache as in the above embodiment, the next update data may be accepted if there is free space in the cache. Thereby, in the above embodiment, the efficiency of the main site and the entire disk array system can be improved. Moreover, since copy processing between the cache and the dedicated buffer does not occur, the processing load of the entire disk array system can be reduced.
Further, in the case of simply copying data between synchronized disk array devices that do not use a buffer, if there is update data in the same area, a write delay of the update data may occur due to cache conflict. In the above embodiment, even when two or more update data to be written to the same area are received, cache contention can be avoided and write delay can also be avoided.

In addition, the above host 10, disk array device 17, and disk array device 27 include a processor, memory, hard disk, SSD (solid state drive), optical drive, optical magnetic drive, transmitter / receiver, display, and keyboard. , A mouse and the like can be provided as needed. In addition, the above components may be implemented by software.

Further, in the above embodiment, the network may be, for example, Ethernet (registered trademark), Fiber Channel, or a wireless communication network. The network may be a LAN (local area network), a WAN (wide area network), the Internet, an intranet, a public line, or the like. Alternatively, the network may be configured by combining a plurality of types of networks.

Other Additional Embodiments Further, other additional embodiments will be shown below.

A disk array system including a first disk array device and a second disk array device.
The first disk array device is
The first cache and
A first I / O processing unit that receives update data from the outside, generates a cache ID corresponding to the update data, and writes the update data to the first cache.
It is provided with a first order guarantee control unit that links cache IDs in the order in which update data is received and generates a link based on the cache ID.
At a predetermined timing, the first order guarantee control unit transmits the update data and the link by the cache ID to the second disk array device, and then
The second disk array device
The second cache and
With the second I / O processing unit that receives the update data from the first disk array device and the link by the cache ID, refers to the link by the cache ID, and writes it to the second cache according to the order in which the update data is received. ,
It is provided with a second order guarantee control unit that writes the update data stored in the second cache at a predetermined timing to a disk according to the order of receiving the update data by referring to the link by the cache ID.
Disk array system.

The first order guarantee control unit generates the attribute information corresponding to the cache ID, sets the attribute information of the update data to the first attribute when storing the update data in the first cache, and further updates. The above-mentioned disk array system that sets the attribute information of the existing update data to the second attribute when the existing update data written to the same area of the disk for the data is stored in the first cache.

The first I / O processing unit is that when the update data is written to the same area of the disk as the existing update data, the existing update data is in the second cache even if the existing update data is in the first cache. The disk array system described above that writes update data to the cache without waiting for it to be sent to the disk array device.

The above-mentioned disk array system in which when update data is transmitted from the first disk array device to the second disk array device, the attribute information of the update data is also transmitted to the second disk array device.

The disk array system described above, in which the disk control unit writes only the update data whose attribute information is the first attribute to the disk according to the order in which the update data is received.

A method for controlling a disk array system in a disk array system including a first disk array device and a second disk array device.
The step that the first disk array device receives the update data from the outside,
A step in which the first disk array device generates a cache ID corresponding to the update data and writes the update data to the first cache.
A step in which the first disk array device links the cache IDs in the order in which the update data is received to generate a link by the cache ID.
The step that the first disk array device sends the update data and the link by the cache ID to the second disk array device,
A step in which the second disk array device receives update data and a link by cache ID from the first disk array device, refers to the link by cache ID, and writes the update data to the second cache according to the order in which the update data is received. ,
The second disk array device includes a step of writing the update data stored in the second cache at a predetermined timing to the disk according to the order of receiving the update data by referring to the link by the cache ID.
How to control a disk array system.

The step of generating the link by the cache ID includes the step of generating the attribute information corresponding to the cache ID.
When the update data is stored in the first cache, in the step of generating the attribute information, the attribute information of the update data is set to the first attribute, and the existing update is written to the same area of the disk for the update data. The disk array system control method described above, which sets the attribute information of existing update data to the second attribute if the data is already stored in the first cache.

In the step of writing the update data to the first cache, if the update data is written to the same area of the disk as the existing update data, the existing update data is the first even if the existing update data is already in the first cache. The control method of the disk array system described above, in which update data is written to the cache without waiting for transmission to the disk array device in 2.

The method for controlling a disk array system described above, further comprising a step of transmitting attribute information of update data to a second disk array device.

The step of writing to a disk is the above-mentioned control method of a disk array system in which only the update data whose attribute information is the first attribute is written to the disk according to the order of receiving the update data.

The first disk array device,
The first cache and
A first I / O processing unit that receives update data from the outside, generates a cache ID corresponding to the update data, and writes the update data to the first cache.
It is provided with a first order guarantee control unit that links cache IDs in the order in which update data is received and generates a link by cache ID.
At a predetermined timing, the first order guarantee control unit sends the update data and the link by the cache ID to the second disk array device to request the storage of the update data.
First disk array device.

Here, FIG. 5 is a drawing showing a configuration of an apparatus corresponding to the above embodiment. See the first embodiment for components. Further, FIG. 6 shows the flow of processing in this embodiment. In step S601, the first I / O processing unit receives the update data from the outside, generates a cache ID corresponding to the update data, and writes the update data to the first cache. In step S602, the first order guarantee control links the cache IDs in the order in which the update data is received to generate a link by the cache ID. In step S603, the first order guarantee control unit transmits the update data and the link by the cache ID to the second disk array device at a predetermined timing to request the storage of the update data.

Further, the description of other additional embodiments will be continued below.

The first order guarantee control unit generates the attribute information corresponding to the cache ID, sets the attribute information of the update data to the first attribute when storing the update data in the first cache, and further updates. The first disk array described above sets the attribute information of the existing update data to the second attribute when the existing update data written to the same area of the disk for the data is stored in the first cache. Device.

The first I / O processing unit is that when the update data is written to the same area of the disk as the existing update data, the existing update data is in the second cache even if the existing update data is in the first cache. The first disk array device described above that writes update data to the first cache without waiting for it to be sent to the disk array device.

The first disk array device described above, which also transmits the attribute information of the update data to the second disk array device when the update data is transmitted from the first disk array device to the second disk array device.

The above disclosure is an example. Therefore, the scope of the present invention should not be construed as confined to the disclosure of the above embodiments and the like.

Some or all of the above embodiments may also be described, but not limited to:

(Appendix 1)
A disk array system including a first disk array device and a second disk array device.
The first disk array device
The first cache and
A first I / O processing unit that receives update data from the outside, generates a cache ID corresponding to the update data, and writes the update data to the first cache.
A first order guarantee control unit that links the cache IDs in the order in which the update data is received to generate a link based on the cache IDs is provided.
At a predetermined timing, the first sequence guarantee control unit transmits the update data and the link by the cache ID to the second disk array device.
The second disk array device
The second cache and
The update data and the link by the cache ID are received from the first disk array device, and the update data is written to the second cache according to the order of receiving the update data with reference to the link by the cache ID. , The second I / O processing unit,
A second order guarantee control unit that writes the update data stored in the second cache at a predetermined timing to a disk in accordance with the order of receiving the update data by referring to the link by the cache ID is provided. do,
Disk array system.

(Appendix 2)
The first order guarantee control unit generates attribute information corresponding to the cache ID, and when storing the update data in the first cache, sets the attribute information of the update data in the first attribute. Further, when the existing update data written to the same area of the disk for the update data is stored in the first cache, the attribute information of the existing update data is set in the second attribute. The disk array system described in Appendix 1.

(Appendix 3)
When the update data is written to the same area of the disk as the existing update data, the first I / O processing unit may use the existing update data even if the existing update data is in the first cache. The disk array system according to Appendix 1 or 2, wherein the update data is written to the first cache without waiting for the update data to be transmitted to the second disk array device.

(Appendix 4)
The disk array according to Appendix 2, wherein when the update data is transmitted from the first disk array device to the second disk array device, the attribute information of the update data is also transmitted to the second disk array device. system.

(Appendix 5)
The disk array system according to Appendix 2 or 4, wherein the second order guarantee control unit writes only the update data whose attribute information is the first attribute according to the order of receiving the update data to the disk.

(Appendix 6)
A method for controlling a disk array system in a disk array system including a first disk array device and a second disk array device.
The step in which the first disk array device receives update data from the outside,
A step in which the first disk array device generates a cache ID corresponding to the update data and writes the update data to the first cache.
A step in which the first disk array device links the cache IDs in the order in which the update data is received to generate a link based on the cache IDs.
A step in which the first disk array device transmits the update data and a link by the cache ID to the second disk array device.
The second disk array device receives the update data and the link by the cache ID from the first disk array device, refers to the link by the cache ID, and updates the update data according to the order of receiving the update data. The step of writing the data to the second cache,
A step in which the second disk array device writes the update data stored in the second cache at a predetermined timing to a disk in accordance with the order of receiving the update data by referring to the link by the cache ID. Equipped with
How to control a disk array system.

(Appendix 7)
The step of generating a link by the cache ID includes a step of generating attribute information corresponding to the cache ID.
When the update data is stored in the first cache, in the step of generating the attribute information, the attribute information of the update data is set to the first attribute, and further, the same area of the disk is set for the update data. The control of the disk array system according to Appendix 6, which sets the attribute information of the existing update data in the second attribute when the existing update data to be written to is already stored in the first cache. Method.

(Appendix 8)
In the step of writing the update data to the first cache, when the update data is written to the same area of the disk as the existing update data, even if the existing update data is already in the first cache, The method for controlling a disk array system according to Appendix 6 or 7, wherein the update data is written to the first cache without waiting for the existing update data to be transmitted to the second disk array device.

(Appendix 9)
The control method of a disk array system according to Appendix 7, further comprising a step of transmitting the attribute information of the update data to the second disk array device.

(Appendix 10)
The control method of a disk array system according to Appendix 7 or 9, wherein the step of writing to the disk follows the order of receiving the update data and writes only the update data whose attribute information is the first attribute to the disk.

(Appendix 11)
The first disk array device,
The first cache and
A first I / O processing unit that receives update data from the outside, generates a cache ID corresponding to the update data, and writes the update data to the first cache.
A first order guarantee control unit that links the cache IDs in the order in which the update data is received to generate a link based on the cache IDs is provided.
At a predetermined timing, the first order guarantee control unit transmits the update data and the link by the cache ID to the second disk array device to request the storage of the update data.
The first disk array device.

(Appendix 12)
The first order guarantee control unit generates attribute information corresponding to the cache ID, and when storing the update data in the first cache, sets the attribute information of the update data in the first attribute. Further, when the existing update data written to the same area of the disk for the update data is stored in the first cache, the attribute information of the existing update data is set in the second attribute. The first disk array device according to Appendix 11.

(Appendix 13)
When the update data is written to the same area of the disk as the existing update data, the first I / O processing unit may use the existing update data even if the existing update data is in the first cache. The first disk array device according to Appendix 11 or 12, wherein the update data is written to the first cache without waiting for the update data to be transmitted to the second disk array device.

(Appendix 14)
The first described in Appendix 12, wherein when the update data is transmitted from the first disk array device to the second disk array device, the attribute information of the update data is also transmitted to the second disk array device. Disk array device.

1 Main site 2 Remote site 10 Data update host 11 I / O processing unit 12 Cache 13 Transmission unit 14 Order guarantee control unit 15 Disk control unit 16 Disk 17 Disk array device 21 I / O processing unit 22 Cache 23 Receiver 24 Order guarantee control Unit 25 Disk control unit 26 Disk 27 Disk array device 30 Remote line

Claims (10)

A disk array system including a first disk array device and a second disk array device.
The first disk array device
The first cache and
A first I / O processing unit that receives update data from the outside, generates a cache ID corresponding to the update data, and writes the update data to the first cache.
A first order guarantee control unit that links the cache IDs in the order in which the update data is received to generate a link based on the cache IDs is provided.
At a predetermined timing, the first sequence guarantee control unit transmits the update data and the link by the cache ID to the second disk array device.
The second disk array device
The second cache and
The update data and the link by the cache ID are received from the first disk array device, and the update data is written to the second cache according to the order of receiving the update data with reference to the link by the cache ID. , The second I / O processing unit,
A second order guarantee control unit that writes the update data stored in the second cache at a predetermined timing to a disk in accordance with the order of receiving the update data by referring to the link by the cache ID is provided. do,
Disk array system. The first order guarantee control unit generates attribute information corresponding to the cache ID, and when storing the update data in the first cache, sets the attribute information of the update data in the first attribute. Further, when the existing update data written to the same area of the disk for the update data is stored in the first cache, the attribute information of the existing update data is set in the second attribute. The disk array system according to claim 1. When the update data is written to the same area of the disk as the existing update data, the first I / O processing unit may use the existing update data even if the existing update data is in the first cache. The disk array system according to claim 1 or 2, wherein the update data is written to the first cache without waiting for the update data to be transmitted to the second disk array device. The disk according to claim 2, wherein when the update data is transmitted from the first disk array device to the second disk array device, the attribute information of the update data is also transmitted to the second disk array device. Array system. The disk array system according to claim 2 or 4, wherein the second order guarantee control unit writes only the update data whose attribute information is the first attribute according to the order of receiving the update data to the disk. .. A method for controlling a disk array system in a disk array system including a first disk array device and a second disk array device.
The step in which the first disk array device receives update data from the outside,
A step in which the first disk array device generates a cache ID corresponding to the update data and writes the update data to the first cache.
A step in which the first disk array device links the cache IDs in the order in which the update data is received to generate a link based on the cache IDs.
A step in which the first disk array device transmits the update data and a link by the cache ID to the second disk array device.
The second disk array device receives the update data and the link by the cache ID from the first disk array device, refers to the link by the cache ID, and updates the update data according to the order of receiving the update data. The step of writing the data to the second cache,
A step in which the second disk array device writes the update data stored in the second cache at a predetermined timing to a disk in accordance with the order of receiving the update data by referring to the link by the cache ID. Equipped with
How to control a disk array system. The first disk array device,
The first cache and
A first I / O processing unit that receives update data from the outside, generates a cache ID corresponding to the update data, and writes the update data to the first cache.
A first order guarantee control unit that links the cache IDs in the order in which the update data is received to generate a link based on the cache IDs is provided.
At a predetermined timing, the first order guarantee control unit transmits the update data and the link by the cache ID to the second disk array device to request the storage of the update data.
The first disk array device. The first order guarantee control unit generates attribute information corresponding to the cache ID, and when storing the update data in the first cache, sets the attribute information of the update data in the first attribute. Further, when the existing update data written to the same area of the disk for the update data is stored in the first cache, the attribute information of the existing update data is set in the second attribute. , The first disk array device according to claim 7. When the update data is written to the same area of the disk as the existing update data, the first I / O processing unit performs the existing update even if the existing update data is in the first cache. The first disk array device according to claim 7 or 8, wherein the update data is written to the first cache without waiting for the data to be transmitted to the second disk array device. The ninth disk array device according to claim 9, wherein when the update data is transmitted from the first disk array device to the second disk array device, the attribute information of the update data is also transmitted to the second disk array device. 1 disk array device.

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