JP2004078999A - Disk storage access system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To disperse an access load to a disk storage from a plurality of computers with respect to SAN disk storage access.
SOLUTION: Access frequency measuring units 124 and 134 measure the frequency of access to disks of their own computers, a resource monitoring management unit 101 inquires resource monitoring units 121 and 131, collects and aggregates the measured access frequencies, and creates a table. When the total access frequency for a certain disk is equal to or greater than the first specified value, the volume control unit 103 requests the SAN control unit 102 to perform volume copying when the total access frequency is equal to or less than the second specified value. In the case of copy, the DKU control unit instructs the copy source DKC to copy the volume to another disk, and in the case of deletion, instructs the delete DKC to delete the copy volume and the SAN control unit. Instructs the LU conversion control units 123 and 133 to change the access path to the disk after the copy and deletion are completed.
[Selection diagram] Fig. 1

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 disk storage access load.

There is known a method in which a plurality of computers and a plurality of disk storages are connected by a dedicated storage network (fiber channel) to share the storage (for example, see Patent Document 1).
This technique is called SAN, and has a feature that the degree of freedom in assigning disks and computers is high, and that a necessary disk area can be flexibly allocated to computers.
2. Description of the Related Art In recent years, information systems using the Internet have become important. In particular, computer systems that construct Web servers and provide contents have increased.
In the case of a Web server, the number of client computers is unspecified and large, access is often concentrated, and its 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 JP-A-10-27147 JP-A-10-69467

In Japanese Patent Application Laid-Open No. Hei 10-27147, access is distributed by dividing content into small pieces and distributing the divided pieces into a plurality of disks.
In this case, the load can be distributed by the number of disks, but it is not possible to cope with a case where the access concentration is higher than predicted in advance.
Further, in Japanese Patent Application Laid-Open No. 10-69467, a plurality of server computers are prepared to perform load distribution, but it is difficult to distribute disk load.
Even in a SAN, a plurality of computers can share a disk, but as the number of computers increases, the load on the shared disk increases, and there is a problem that 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 situation where loads from a plurality of computers are concentrated in a SAN and the load of access to a disk storage changes.

In order to achieve the above object, in the present invention, each computer referring to the disk is provided with a measuring means for measuring the frequency of access to the disk, and the frequency of access to the same disk measured by each computer is collected and tabulated. When the access frequency of the counting result is higher than a predetermined access frequency, the copy source disk is instructed to copy the contents of the disk to one or more other disks, and after receiving a copy completion report, Instruction means for instructing the computer accessing the disk to change the access path from the copy source disk to the copy destination disk to the disk, and further, the access path from the instruction means to each computer referring to the disk. A means for switching the access path from the computer to the disk in response to the instruction to change the To have.

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

(4) When the contents of the copy source disk are changed, the changed contents of the copy source disk 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 by 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 the disk access management system.

This system is composed of a management computer (100) and a SAN management computer (110) that manages the SAN (140), a SAN reference computer 1 (120) accessing 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).

This 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 a 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. It has a management table (103) and a SAN control unit (102) for issuing a request to the SAN.

The SAN management computer (110) includes a DKU control unit (111) for instructing copying and deletion of a volume according to a request from the SAN control unit (102).

The SAN reference computer 1 (120) and the SAN reference computer 2 (130) have application programs (122) and (132) for accessing the disk of the SAN (140), and an LU (Logical Unit) for controlling the disk access path of the application program. ) Conversion control units (123), (133), LU conversion tables (125), (135) used for managing disk access paths, access frequency measurement units (124), (134) for measuring disk access frequency, Resource monitoring units (121) and (131) are provided for responding to the resource monitoring management unit (101) of disk access frequency.

Disk devices are connected to the SAN (140). These include DKCs (151) and (161) which are disk control devices, a volume control unit (152) for controlling a volume (logical volume) of the disk, and ( 162), and disk units (DKU) (153) and (163), which are actual disk storages.

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

The resource monitoring management unit (101) periodically inquires of the resource monitoring units (121, 131) about the access frequency of the disk units (200), and checks the disk units responded from the resource monitoring units (121, 131). The access frequency data is totaled in the access frequency management table (103) (202).

If the access frequency of the disk unit exceeds the set high threshold value (204), the resource monitoring management unit (101) sends a request from the disk unit to the SAN control unit (102) for one or more other disk units. (206).

When the access frequency of the disk unit falls below the set low threshold value (208), and when data is copied to one or more disk units (210), the SAN control unit (102) is A request is made to delete the volume of one or more disk units (214).

し な い Otherwise, do nothing (212).

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

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

(4) When a volume copy request is accepted, the DKU control unit (111) is requested to perform a volume copy 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 LU conversion control unit (135) of the SAN reference computer 2 (130), which has the highest access frequency, sends the access path using the copy source. A request is made to change from a certain disc X to a copy destination disc Y (308).

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

When the volume deletion request is accepted, the LU conversion control unit (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). ).

(5) Thereafter, a request is made to the DKU control unit (111) to delete the copy destination volume (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.

(4) When the contents of the copy source disk X are changed, the copy from the copy source disk X to the disk Y is performed again by the command of the SAN management computer. If there are a plurality of copy destinations, copying from the copy source disk X to a plurality of copy destination disks is performed again.

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

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

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

After receiving the notification of the completion of the volume copy from the DKC (151) (406), it notifies the SAN control unit (102) of the request source of the completion of the volume copy (408).

(4) If a volume deletion request has been received, a volume deletion request for the disk unit is issued to the DKC (151) (410).

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

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

(4) Respond the collected data to the resource monitoring management unit (101) (504).

FIG. 6 shows a flowchart of the LU conversion control section (123, 133).

The LU conversion control unit receives the request (600) and performs processing according to the request (602).

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

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

Send an access request to the DKC corresponding to the determined access path (608).

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

When receiving the access frequency acquisition request (700), the access frequency measurement units (124, 134) calculate the access frequency from the measured data of the number of accesses to each disk or the amount of access data (702), and use the access frequency as the request source. Responds (704).

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

The LU conversion table is a correspondence table that exists in each computer that uses the SAN, and that corresponds to the LU number accessed by the application program and the DKU number indicating the target disk.

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

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

ＤThe 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 the access frequency collected from each computer to the SAN disk.

For example, the access frequency to the disk X is managed as the one obtained from the SAN reference computer 1 (901) and the one obtained from the SAN reference computer 2 (902).

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

(6) The access frequency of the data managed in FIG. 9 is totaled for each disk unit and displayed.

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

。 Also displays the minimum, maximum, and average values of the collected and stored data.

Although the embodiments of the present invention have been described above, the DKU control unit in the SAN management computer shown in FIG. 1 may be moved to the management computer, and the configuration of the management computer may be adopted.

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.

(4) Further, the means may be provided in one of the plurality of SAN reference computers.

FIG. 1 is a diagram showing an example of the overall configuration of a system according to the present invention. 5 is a flowchart illustrating processing of a resource monitoring management unit according to the present invention. 5 is a flowchart illustrating processing of a SAN control unit according to the present invention. 5 is a flowchart illustrating processing of a DKU control unit according to the present invention. 5 is a flowchart illustrating processing of a resource monitoring unit according to the present invention. 5 is a flowchart illustrating a process of an LU conversion control unit according to the present invention. 5 is a flowchart illustrating processing of an access frequency measurement unit according to the present invention. FIG. 11 is a diagram showing a format example of an LU conversion table of a computer accessing the SAN according to the present invention. FIG. 4 is a diagram showing a format example of an access frequency management table in the management computer according to the present invention. FIG. 14 is a diagram showing an example of a screen displaying access frequencies tabulated by the management computer according to the present invention.

Explanation of reference numerals

Reference Signs List 100 management computer 101 resource monitoring management unit 102 SAN control unit 103 access frequency management table 110 SAN management computer 111 DKU control unit 120, 130 SAN reference computer 121, 131 resource monitoring unit 122, 132 application program 123, 133 LU conversion control unit 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 (6)

An access system of a disk storage shared and accessed by a plurality of computers, wherein each computer referring to the disk includes a measuring unit for measuring an access frequency to the disk, and an access frequency to the same disk measured by each computer. When the access frequency in the result of the aggregation is higher than a predetermined access frequency, an instruction is given to the disk to copy the contents of the disk to one or more other disks, and a copy completion report is received. And instructing the computer accessing the post-copy source disk to change the access path from the copy source disk to the copy destination disk to the disk. Receives an instruction to change the access path from the computer, and accesses the disk from the computer according to the instruction. Disk storage access system, characterized in that it comprises means for switching the scan. に お い て The disk storage access system according to claim 1, wherein said instruction means is provided in any one of a plurality of computers. An access system for a disk storage shared and accessed by a plurality of computers, comprising a plurality of computers referring to a disk and a management computer, wherein each computer referring to the disk measures a frequency of access to the disk. The management computer collects and tabulates the access frequency to the same disk measured by each computer, and when the access frequency of the total result is higher than a predetermined access frequency, the content of the disk with respect to the disk To the one or more other disks, and, after receiving the copy completion report, instruct the computer accessing the copy source disk from the copy source disk to the copy destination disk. Means for instructing the change, and each computer referring to the disk accesses the disk from the management computer. Receiving an instruction to change the 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. An access system for a disk storage shared and accessed by a plurality of computers, comprising a plurality of computers referring to disks, a first management computer, and a second management computer, wherein each computer referring to the disks is Measuring means for measuring the frequency of access to the disk; the first management computer collects and tabulates the frequency of access to the same disk measured by each computer; When the value is higher, a means for sending an instruction to copy the contents of the disk to one or more other disks is provided to the second management computer, and the second management computer receives the instruction and Means for instructing to copy the contents of the disk to one or more other disks, wherein the first management computer has a copy completion command from the second management computer. When receiving the report, the computer which has accessed the copy source disk is provided with means for 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. And a means for receiving an instruction to change an access path from the first management computer and switching an access path from the computer to the disk in accordance with the instruction. 5. The disk storage access system according to claim 1, wherein the computer accessing the copy source disk accesses the disk from the copy source disk to the copy destination disk. An access system for a disk storage, wherein when an instruction to change a path is issued, the instruction is issued to a computer having the highest access frequency to the copy source disk. 5. The disk storage access system according to claim 1, wherein when the contents of the copy source disk are changed, the changed contents of the copy source disk are stored in one or more of the copy destinations. An access system for a disk storage, which is copied to a disk again.

Images