JP4172384B2 - Disk storage access system - Google Patents

Description

The present invention relates to SAN (Storage Area Network) disk storage access, and more particularly to a disk storage access system that distributes the access load of the disk storage.

A method of sharing a storage by connecting a plurality of computers and a plurality of disk storages via a storage-dedicated network (Fibre Channel) is known (for example, see Patent Document 1).
This technique is called SAN, and has a feature that it has a high degree of freedom in allocation of disks and computers, and can flexibly allocate necessary disk areas to computers.
In recent years, information systems using the Internet have become important, and in particular, computer systems that provide contents by constructing Web servers have increased.
In the case of a Web server, the number of client computers is unspecified, and access often concentrates, and the peak is often unpredictable.
As a method for distributing access to a computer system, a method disclosed in Patent Document 2 and a method disclosed in Patent Document 3 are known.

JP 2000-99272 A Japanese Patent Laid-Open No. 10-271447 JP-A-10-69467

In Japanese Patent Laid-Open No. 10-271447, access is distributed by dividing the content into small pieces and distributing them to a plurality of disks.
In this case, the load can be distributed as many as the number of disks, but it cannot be handled when there is more access concentration than previously predicted.
Japanese Patent Laid-Open No. 10-69467 prepares a plurality of server computers for load distribution, but it is difficult to distribute the load on the disk.
Even in a SAN, a disk can be shared by a plurality of computers. However, when the number of computers increases, there is a problem that the load of the shared disk increases and the performance cannot be maintained.
An object of the present invention is to provide a disk access load distribution method that can flexibly cope with a case where loads from a plurality of computers are concentrated in a SAN and a load of access to a disk storage changes.

  In order to achieve the above object, in the present invention, each computer that refers to a disk is provided with a measuring means for measuring the access frequency to the disk, and the access frequency to the same disk measured by each computer is collected and aggregated. When the access frequency of the counting result is higher than a predetermined access frequency, the disk is instructed to copy the contents of the disk to one or more other disks, and after receiving a copy completion report, the copy source disk Is provided with instruction means for instructing the computer that has been accessing the disk to change the access path to the disk from the copy source disk to the copy destination disk, and the access path from the instruction means to each computer that refers to the disk In response to this instruction, a means for switching the access path from the computer to the disk is provided. There.

  Also, when instructing the computer that has accessed the copy source disk to change the access path to the disk from the copy source disk to the copy destination disk, this instruction is the most frequently accessed access to the copy source disk. I try to do it for the expensive computer.

  Further, when the copy source disk contents are changed, the changed copy source disk contents are copied again to one or more copy destination disks.

According to the present invention, it is possible to distribute the load of a disk accessed from a plurality of computers, and to flexibly cope with a change in load.

  An embodiment of the present invention will be described below with reference to the drawings.

  FIG. 1 is an overall configuration diagram of a disk access management system.

  This system includes a management computer (100) and a SAN management computer (110) that manages the SAN (140), a SAN reference computer 1 (120) that accesses a SAN disk, and a SAN reference computer 2 (130). . The management computer (100) is connected to the SAN management computer (110), the SAN reference computer 1 (120), and the SAN reference computer 2 (130) via the LAN (170).

  The system controls access to the SAN (140) disk by managing the access frequency to the disk from the SAN reference computer 1 (120) and the SAN reference computer 2 (130) by the management computer (100).

  The management computer (100) includes a resource monitoring management unit (101) that manages the disk access frequency in the SAN reference computer 1 (120) and the SAN reference computer 2 (130), and an access frequency used to manage the disk access frequency. A management table (103) and a SAN control unit (102) for issuing a request to the SAN are provided.

  The SAN management computer (110) includes a DKU control unit (111) that instructs volume copy and deletion in accordance with a request from the SAN control unit (102).

  The SAN reference computer 1 (120) and the SAN reference computer 2 (130) include application programs (122) and (132) that access the disks of the SAN (140), and LUs (Logical Units) that control the disk access paths of the application programs. ) Conversion control units (123), (133), LU conversion tables (125), (135) used for managing disk access paths, access frequency measurement units (124), (134), which measure disk access frequency, Resource monitoring units (121) and (131) are provided which respond to the disk access frequency to the resource monitoring management unit (101).

  A disk device is connected to the SAN (140), and includes DKC (151) and (161) which are disk control devices, a volume control unit (152) which controls a disk volume (logical volume), ( 162) and disk units (DKU) (153) and (163) which are actual disk storages.

  FIG. 2 shows a flowchart of the resource monitoring management unit (101).

  The resource monitoring management unit (101) periodically inquires the access frequency of the disk unit to the resource monitoring unit (121, 131) (200), and the disk unit returned from the resource monitoring unit (121, 131) The access frequency data is tabulated in the access frequency management table (103) (202).

  When the access frequency of the disk unit exceeds the set high threshold (204), the resource monitoring management unit (101) sends one or more other disk units from the disk unit to the SAN control unit (102). Request volume copy to (206).

  When the access frequency of the disk unit falls below the set low threshold (208), and when data is copied to one or more disk units (210), the SAN control unit (102) Request deletion of volumes of one or more disk units (214).

  Otherwise, do nothing (212).

  FIG. 3 shows a flow chart of the SAN control unit (102).

  The SAN control unit (102) receives a request from the resource monitoring management unit (101) (300), and performs processing according to the request content (302).

  When the volume copy request is received, the DKU control unit 111 is requested to copy the volume from the disk unit to one or more other disk units (304).

  After receiving the volume copy completion notification from the DKU control unit (111) (306), the access path is transferred to the LU conversion control unit (135) of the SAN reference computer 2 (130) having the highest access frequency at the copy source. A request is made to change from a certain disk X to a disk Y as a copy destination (308).

  For example, when there are three or more SAN reference computers, the access paths are averaged by switching the access paths of the SAN reference computers having the highest access frequency.

  When the volume deletion request is received, the LU conversion controller (135) of the SAN reference computer 2 (130) is requested to change the access path from the copy destination disk Y to the copy source disk X (310). ).

  Thereafter, it requests the DKU controller (111) to delete the volume that was the copy destination (312).

  In the present invention, since the main purpose is to refer to contents such as a Web server, the data in the copied disk is not directly updated from the SAN reference computer.

  When the contents of the disk X as the copy source are changed, copying from the disk X as the copy source to the disk Y is performed again in response to an instruction by a command to the SAN management computer. If there are a plurality of copy destinations, copying is performed again from the copy source disk X to the copy destination disks.

  FIG. 4 shows a flowchart of the DKU control unit (111).

  The DKU control unit (111) receives a request from the SAN control unit (102) (400), and performs processing according to the request (402).

  If a volume copy request is received, a volume copy request is issued to the DKC (151) (404).

  After receiving the volume copy completion notification from the DKC (151) (406), the volume control completion is notified to the requesting SAN control unit (102) (408).

  If a volume deletion request is accepted, a disk unit volume deletion request is issued to the DKC (151) (410).

  FIG. 5 shows a flowchart of the resource monitoring unit (121, 131).

  The resource monitoring unit (121, 131) receives the inquiry from the resource monitoring management unit (101) (500), and collects the disk access frequency from the access frequency measurement unit (124, 134) (502).

  The collected data is returned to the resource monitoring management unit (101) (504).

  FIG. 6 is a flowchart of the LU conversion control unit (123, 133).

  The LU conversion control unit receives the request (600) and performs processing in accordance with the request (602).

  When an LU conversion table rewrite request is received, the LU conversion table (125, 135) is changed according to the request source instruction, and the disk access path is changed (604).

  When a disk access request from the application program is received, the LU conversion table (125, 135) is searched to determine the disk access path (606).

  An access request is sent to the DKC corresponding to the determined access path (608).

  FIG. 7 shows a flowchart of the access frequency measurement unit.

  When the access frequency measurement unit (124, 134) receives an access frequency acquisition request (700), the access frequency measurement unit (124, 134) calculates the access frequency from the measurement data of the access count or access data amount of each disk (702), and uses the access frequency as the request source. Answer (704).

  FIG. 8 shows the format of the LU conversion table (125, 135).

  The LU conversion table is a correspondence table of an LU number that is present in each computer using a SAN and accessed by an application program and a DKU number indicating the target disk.

  First, in the LU conversion table of the SAN reference computer 1, the DKU number corresponding to LU number 1 is X (801), and the DKU number corresponding to LU number 2 is Y (802).

  In the LU conversion table of the SAN reference computer 2, the DKU number corresponding to LU number 1 is X. However, the access frequency exceeds the high threshold value, volume copying is performed, and the DKU number is rewritten from X to Y (811). ).

  The DKU number corresponding to LU number 2 is Z.

  FIG. 9 shows the format of the access frequency management table (103).

  The access frequency management table manages a collection of access frequencies for SAN disks from each computer.

  For example, the access frequency for the disk X is managed from the SAN reference computer 1 (901), and the access frequency is also acquired from the SAN reference computer 2 (902).

  FIG. 10 shows an example of a screen that displays the access frequency.

  The access frequency of the data managed in FIG. 9 is tabulated and displayed for each disk unit.

  Displays the time when data was collected and the frequency of access to the disk at that time.

  It also displays the minimum, maximum, and average values of the collected and stored data.

  The embodiment of the present invention has been described above. However, the DKU control unit in the SAN management computer shown in FIG. 1 may be moved to the management computer to configure the management computer.

  Further, instead of the management computer and the SAN management computer shown in FIG. 1, one means having a SAN control unit, a resource monitoring management unit, an access frequency management table in the management computer, and a DKU control unit in the SAN management computer is provided. May be.

  Further, the means may be provided in one SAN reference computer among a plurality of SAN reference computers.

It is the figure which showed the example of whole system structure by this invention. It is a flowchart explaining the process of the resource monitoring management part in this invention. It is a flowchart explaining the process of the SAN control part in this invention. It is a flowchart explaining the process of the DKU control part in this invention. It is a flowchart explaining the process of the resource monitoring part in this invention. It is a flowchart explaining the process of the LU conversion control part in this invention. It is a flowchart explaining the process of the access frequency measurement part in this invention. It is the figure which showed the example of a format of LU conversion table of the computer which accesses SAN by this invention. It is the figure which showed the example of a format of the access frequency management table in the management computer by this invention. It is the figure which showed the example of the screen which displays the access frequency totaled with the management computer by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Management computer 101 Resource monitoring management part 102 SAN control part 103 Access frequency management table 110 SAN management computer 111 DKU control part 120, 130 SAN reference computer 121, 131 Resource monitoring part 122, 132 Application program 123, 133 LU conversion control part 124 134 Access frequency measurement unit 125, 135 LU conversion table 140 SAN
151, 161 Disk controller 152, 162 Volume controller 153, 163 Disk unit 170 LAN

Claims (5)

A disk storage access system that is shared and accessed from a plurality of computers, wherein each computer that refers to a disk is provided with a measuring means for measuring the access frequency to the disk, and the access frequency to the same disk measured by each computer aggregates collect, when the access frequency of the counting result is higher than the access frequency with predetermined instructs to copy the contents of the disk to the other one or more disks with respect to the disk, receiving the copy completion report After that, instruct the computer that accessed the copy source disk with the highest access frequency to the copy source disk to change the access path from the copy source disk to the copy destination disk. Each computer that includes an instruction unit and refers to the disk has an access path from the instruction unit. Receiving an instruction to change, disk storage access system, characterized in that it comprises means for switching the access path from the computer in response to the instruction to the disk.   2. The disk storage access system according to claim 1, wherein the instruction means is provided in any one of a plurality of computers. A disk storage access system shared by a plurality of computers and having a plurality of computers that refer to the disks and a management computer, and each computer that refers to the disks measures the frequency of access to the disks The management computer collects and aggregates the access frequency to the same disk measured by each computer, and when the access frequency of the aggregation result is higher than a predetermined access frequency, the contents of the disk with respect to the disk Is copied to the computer with the highest frequency of access to the copy source disk after accessing the copy source disk after receiving the copy completion report. Means to change the access path from the original disk to the copy destination disk And a disk storage access system comprising: a computer that refers to a disk, and receives an instruction to change an access path from the management computer; and a means for switching an access path from the computer to the disk in accordance with the instruction. . A disk storage access system that is shared and accessed from a plurality of computers, and includes a plurality of computers that reference a disk, a first management computer, and a second management computer. The first management computer collects and aggregates the access frequencies to the same disk measured by each computer, and the access frequency of the aggregation result is a predetermined access frequency. Means for sending to the second management computer an instruction to copy the contents of the disk to one or more other disks when the instruction is higher, the second management computer receiving the instruction Means for instructing to copy the contents of the disk to one or more other disks, and the first management computer completes copying from the second management computer. When subjected to tell, changes the access path to the disk from the copy source disk to the access frequency to the copy source disk of the computer that was accessed source disc is highest was computer to the copy destination disk And each computer that refers to the disk receives an instruction to change the access path from the first management computer, and includes means for switching the access path from the computer to the disk in accordance with the instruction. Disk storage access system characterized by 5. The disk storage access system according to claim 1, wherein when the copy source disk content is changed, the changed copy source disk content is changed to one or more of the copy destinations. A disk storage access system characterized by copying to a disk again.

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