JP2003029935A - Storage system and storage system management method for storage system - Google Patents

Abstract

(57) [Problem] To provide a technology for effectively utilizing an unused portion of a physical storage device in a storage system. A disk array system includes a plurality of parity groups each including a plurality of physical storage devices. Multiple physical storage devices 1
Any one of 510 includes an unused area to which no logical address is assigned. When the physical storage device 1510 is replaced, the address management unit 1320 allocates a logical address to an unused area of all the physical storage devices 1510 in the parity group 1520 up to the smallest storage capacity among the physical storage devices 1510.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a storage system having a plurality of storage devices, and more particularly to a storage system that increases the usable area when the capacity of the storage device increases.

[0002]

2. Description of the Related Art In a computer system, a storage system represented by a disk array system is one of the secondary storage systems that realizes high performance. The disk array system arranges a plurality of physical storage devices in an array and executes reading / writing of data stored in a divided manner in each physical storage device in parallel. As a result, data input / output can be performed at high speed.

As a paper on the disk array system, D. A. Patterson, G.M. Gibso
n, and R.N. H. Kats, "A Case f
orRedundant Arrays of Ine
xpensive Disks ”
(In Proc. ACM SIGMOD, pp.
109-116, June 1988). In the disk array system shown here, the levels corresponding to the levels of redundancy from level 1 to level 5 are set.
Further, a disk array system without redundancy may be called level 0. The cost, performance characteristics, etc. for configuring the system differ depending on the redundancy. Therefore, in one disk array system, different redundancy levels can be set for each of a plurality of physical storage device groups. Here, this physical storage device group is called a parity group.

The cost of the physical storage device itself also differs depending on the performance and capacity. Therefore, when constructing a disk array system, a plurality of types of physical storage devices having different performances or capacities may be used in order to obtain the optimum cost performance.

Since the data stored in the disk array system is distributed and arranged in the physical storage device as described above, the disk array system has a logical storage area accessed by a host computer connected to the disk array system and the physical storage device. The physical storage area indicating the storage area of the storage device is associated (address conversion).

Japanese Unexamined Patent Publication No. 2000-293317 discloses I for a logical storage area from a host computer.
A disk array system that realizes the optimum placement of stored data by means for acquiring information about I / O access and means for physically rearranging by changing the correspondence between the logical storage area and the physical storage area As shown therein, an empty logical storage area is prepared for optimal allocation of stored data, and the optimal allocation of data is realized by copying the data to the logical storage area.

Further, in the US Pat. No. 6,061,761, the disk array configuration can be dynamically changed from the one in which the disk array configuration was manually changed to distribute the load of the conventional disk array system. The method that enables load distribution by setting and the method that enables load distribution on a physical storage area that includes logical storage areas of different sizes are shown, and as an optimal allocation of data for load distribution, A pair of logical storage areas is prepared for the logical storage area storing the data, and the mirror function is used to realize the optimum data arrangement.

On the other hand, the physical storage devices used in the disk array system continue to increase in performance, increase in capacity and decrease in price year by year, and the physical storage devices used in the past have a high unit price per bit and high performance. Bad things are preventing manufacturers from making such old physical storage devices.
Therefore, when the physical storage device used in the conventional disk array system becomes unusable due to a failure or the like, a new large-capacity physical storage device is used as a substitute.

On the other hand, a method of providing a storage area to a user who purchases a disk array system is such that when the user buys only the required storage capacity and later the user needs more storage capacity, the parity group unit is used. Is being done in.

[0010]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
The following problems exist in optimal data placement in a disk array system, which is one of secondary storage systems, as disclosed in Japanese Patent No. 293317 and US Pat. No. 6,061,761.

First, in both methods, a process of rearranging certain data in another logical storage area is performed for optimum data arrangement. However, the logical storage areas of other relocation destinations are not distinguished from the areas that originally store data, and if some processing has not been performed on the logical storage area in advance, the relocated data will be placed in the logical storage area. It is a logical storage area in which completely different data may be stored before being executed. However, in that case, when the data is relocated from another logical storage area, the previously existing data may be overwritten / erased. The storable logical storage area cannot store data other than the optimally arranged data for optimal arrangement. For this reason, the disk array system to which the optimum data allocation processing method is applied cannot use the logical storage area, which is the data area, as the data area due to the optimum data allocation from the storage capacity initially provided to the user. Alternatively, it is necessary to introduce a new storage device for optimal data allocation.

If the user who purchases the disk array system wants more capacity than at the time of purchase, the capacity is increased, but this is done only in the parity group unit, and the storage area in the unused parity group is used. Cannot be provided.

Further, new physical storage devices used as replacements for old failed physical storage devices often have larger capacities than the physical storage devices used before. When each physical storage device forming a parity group is replaced with a large-capacity replacement product, all the physical storage devices forming a parity group will eventually be replaced by the replacement physical storage device. Even at this time, the parity group cannot use more storage capacity than that used before, and the increase in storage capacity remains unused.

Therefore, an object of the present invention is to provide a technique for effectively utilizing the unused portion.

[0015]

In order to achieve the above object, the present invention performs the following processing. That is, in a storage system including a plurality of parity groups including a plurality of storage devices, any of the plurality of storage devices in one parity group has an unused area. Of the plurality of storage devices in the one parity group, up to the storage capacity of the storage device having the smallest capacity, logical addresses are assigned to the unused areas of all the storage devices in the parity group.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments to which the present invention is applied will be described below with reference to the drawings.

FIG. 1 is a diagram showing the functional configuration of a computer system according to an embodiment of the present invention. This computer system includes a host computer (hereinafter referred to as a host) 100.
0, disk array system 1 which is a secondary storage system
200 and a control terminal 1700. Host 1
000 may be provided in plural as shown in FIG.
It may be one. The disk array system 1200 has 1
It comprises one or more disk array control devices 1300 and storage devices 1500.

The host 1000, disk array controller 1300 and control terminal 1700 are connected by a network 1900. As an example of the network 1900, Ethernet (registered trademark of Fuji Xerox Co., Ltd.),
FDDI and Fiber Channel.

The host 1000, disk array controller 1300, and control terminal 1700 are all configured by a computer system. Each configuration or each function described below is realized, for example, by executing a program.

Each host 1000 is connected to a disk array controller 1300 by an I / O bus 1800.
Each host 1000 has a disk array system 1200
For data read and write processing,
Issue / O. At the time of this I / O, the host 1000 designates a logical storage area of the disk array system 1200. That is, the host 1000 accesses the data in the disk array system 1200 through the address of the logical storage area. In addition, I / O bus 1800
Examples of are CON, SCSI, Fiber Channel, and the like.

The control terminal 1700 is a terminal device used for maintenance and management of the disk array system 1200. The control terminal 1700 is the logical storage device 1.
Storage device setting means 171 for setting 540 (see FIG. 2)
Equipped with 0. Maintenance of the disk array system 1200,
When performing management, setting of the storage device 1500, and the like, maintenance personnel use the control terminal 1700.

The storage device 1500 comprises a plurality of physical storage devices 1510. Each physical storage device 1510 is a device for recording data, such as a hard disk. This physical storage device 1510 constitutes one parity group 1520 with n units (n ≧ 1). Physical storage device 151
The data stored in 0 is the disk array controller 13
Stored in the parity group 1520 with redundancy under the control of 00.

Here, the disk array controller 1300
Manages and controls the physical storage device 1510 in the storage device 1500 as a logical storage device. Then, each host 1000 designates an address on a logical storage device to access. In this embodiment, a virtual storage device is further provided between the physical storage device 1510 and the logical storage device shown to the user. The conceptual diagram is shown in FIG. That is, the virtual storage device 1530 is allocated between the logical storage device 1540 and the physical storage device 1510 that are visible to the user.

For example, a virtual storage device 1530 is formed as one continuous storage area space for each parity group 1520. The virtual storage device 1530 may be formed by collectively using a plurality of parity groups 1520, or by dividing one parity group 1520 into some. The disk array control device 1300 emulates a disk type corresponding to the host 1000 that accesses the host 1
A logical storage device 1540 is generated by allocating a storage area that can be accessed by 000. Logical storage device 1
540 is assigned to the virtual storage device 1530.

The disk array controller 1300 comprises an optimum placement processing section 1310, an address management section 1320, and a configuration information storage section 1400.

The optimum arrangement processing unit 1310 performs optimum arrangement for optimum arrangement of data in the disk array system 1200 based on indexes such as access frequency and performance. Specifically, the optimum placement processing unit 1310 performs a read / write process of the storage device 1500, a process of obtaining usage status information of the storage device 1500, a process of determining whether to relocate data in the storage device 1500, and , Rearrangement processing is performed.

The address management unit 1320 performs the above-described processing for forming the virtual storage device 1530. The address management unit 1320 registers the attribute information of the formed virtual storage device 1530 in the virtual storage attribute table 1430, and associates the virtual storage device 1530 with the physical storage device 1510.
The configuration information storage unit 1400 is updated by registering in the physical / virtual storage correspondence table 1420.

Further, the address management unit 1320 performs a process of forming the logical storage device 1540. The address management unit 1320 registers the attribute information of the formed logical storage device 1540 in the logical storage attribute table 1440, and registers the correspondence between the virtual storage device 1530 and the logical storage device 1540 in the logical / virtual storage correspondence table 1410. Then, the configuration information storage unit 1400 is updated.

The address management unit 1320 performs processing for securing a reserved area. Details of this processing will be described later.

The optimum placement processing unit 1310 and the address management unit 1320 are provided in the disk array system either in a single unit or in plural units to improve the reliability and performance of the entire system.

The configuration information storage unit 1400 comprises a logical / virtual storage correspondence table 1410, a physical / virtual storage correspondence table 1420, a virtual storage attribute table 1430, a logical storage attribute table 1440, and a parity group attribute table 1460. .

The logical / virtual memory correspondence table 1410 is
Address of virtual storage device 1530 and logical storage device 154
It is a table in which addresses 0 are associated with each other. An example of the logical / virtual memory correspondence table 1410 is shown in FIG.

The logical / virtual memory correspondence table 1410 is
In this embodiment, one table 2000 is configured for one logical storage device 1540. Therefore, the logical / virtual storage correspondence table 1410 is stored in the logical storage device 1540.
Several tables 2000 are provided, and a logical storage device number 2100 is assigned to each table 2000. Then, each table 2000 stores the logical storage device address 23
00 is associated with the virtual storage device number 2210 and the virtual storage device address 2220.

The logical storage device address 2300 is an address assigned to the logical storage device 1540, and is used when each host 1000 accesses the disk array system 1200. The virtual storage device number 221 is a number assigned to the virtual storage device 1530, and the virtual storage device address 2220 is an address in each virtual storage device 2210.

As a result, the address of the logical storage space formed by the logical storage device 1540 is associated with the address of the virtual storage space formed by the virtual storage device 1530.

The physical / virtual memory correspondence table 1420 is
Address of virtual storage device 1530 and physical storage device 151
It is a table in which addresses 0 are associated with each other. FIG. 5 shows an example of the physical / virtual storage correspondence table 1420.

The physical / virtual memory correspondence table 1420 is
In this embodiment, one table 4000 is configured for one virtual storage device 1540. Therefore, the physical / virtual storage correspondence table 1420 is stored in the virtual storage device 1540.
A table for several minutes 4000 is provided, and a virtual storage device number 4100 is assigned to each table 4000. Then, each table 4000 has a virtual storage device address 42
00, device number 4310 of physical storage device, address 4
320, a parity group number 4330, and a used / unused section 4400 are associated with each other.

The device number 4310 and address 4320 of the physical storage device are the device number assigned to the physical storage device 1510 and the address on each device.

The used / unused section 4400 indicates whether the corresponding virtual storage area and physical storage area are used or unused. Here, “used” means used as an area for the host 100 to use. The unused area means an area which the physical storage device 1510 has as a storage area but is not actually used by the host 100. The unused area occurs, for example, in the following cases. That is, the physical storage device 1510
Is replaced and a storage device having a larger capacity than that before replacement is used, the increased capacity usually becomes an unused area.

As a result, the virtual storage space formed by the virtual storage device 1530 is associated with the physical storage device.

Further, for access from the host 1000, the control terminal 1700, etc., address conversion is performed using the logical / virtual storage correspondence table 1410 and the physical / virtual storage correspondence table 1420. As a result, data read / write processing can be accurately performed on the physical storage device 1510.

The virtual storage attribute table 1430 is a table showing the attributes of the virtual storage device 1540. FIG. 6 shows an example of the virtual memory attribute table 1430. The virtual storage attribute table 1430 has a device number 510 of the virtual storage device.
0, the total storage area address space 5200, and the used storage area address space 5300.

The device number 5100 is the device number of the virtual storage device. The entire storage area address space 5200 is an address of the entire storage space of the virtual storage device 1530 indicated by the device number 5100. Used storage area address space 5300
Is an address used as a logical storage area in the entire storage area.

As a result, it becomes possible to associate the capacity possessed by each virtual storage device with the used capacity.

The logical storage attribute table 1440 is a table showing the attributes of the logical storage device 1510. An example of the logical storage attribute table 1440 is shown in FIG. The logical storage attribute table 1440 includes a logical storage device number 3100,
Storage capacity 3200 and emulation type 3300
And a host side path 3400.

The logical storage device number 3100 is a number assigned to each logical storage device 1540. Memory capacity 3
200 is the storage capacity of each logical storage device 1540.
The emulation type 3300 is the logical storage device 15
This is an emulation type for the host 1000 connected to 40. The host side path 3400 indicates whether the logical storage device 1540 has actually set a path to the host. Here, host side pass 3
If 400 is "Yes", the path is actually set,
The logical storage device 1540 is accessible from the host.

This makes it possible to associate the capacity of each logical storage device 1540 with the emulation type.

Parity group attribute table 1460
Is a table showing the attributes of each parity group.
FIG. 7 shows an example of the parity group attribute table 1460. The parity group attribute table 1460 includes a parity group number 6100 and a RAID level 6200.
, The number of physical storage devices 6300, and the minimum storage capacity 640
0 and a parity group capacity (data) 6500.

The parity group number 6100 is the number of the parity group 1520. The parity group number 6100 is determined by the physical location of the physical storage devices that make up the parity group 1520. The raid level 6200 indicates the raid level of each parity group 1520. The number of physical storage devices 6300 is equal to the number of physical storage devices 151 in each parity group 1520.
Indicates whether it is configured by 0. Minimum storage capacity 64
00 indicates the capacity of the smallest capacity storage device among the physical storage devices 1510 that form the parity group 1520. The capacity (data) 6500 of the parity group indicates the storage capacity used by each parity group 1520 as an area for storing data. For example, the capacity of the parity group of the parity group 0 is calculated as 3 (GByte) × 4 (the number of physical storage devices forming the primary volume of RAID 1) = 12 (GBite).

In addition to the above information, the configuration information storage section 1400 may include physical disk attribute information such as physical storage performance information.

Next, each processing flow in the system according to this embodiment will be described. FIG. 8 shows a processing procedure for forming the logical storage device 1540.

The address management unit 1320 creates a virtual storage device 1530 using one or more parity groups (S101). Then, the address management unit 1320
Of the created virtual storage device 1530
The virtual storage correspondence table 1420 and the virtual storage attribute table 1430 are updated (S102).

The address management unit 1320 allocates an address of the logical storage area in order to appropriately emulate the virtual storage space provided by the virtual storage device 1530 according to the type of the host 1000. To generate the logical storage device 1540 (S103). Then, the address management unit 1320, for the generated logical storage device 1540, the logical / virtual storage correspondence table 1
410 and the logical storage attribute table 1440 are updated (S104).

Then, it is judged whether or not the required capacity of the logical storage device 1540 has been secured, and steps S103 to S104 are repeated until secured (S10).
5).

FIG. 9 shows a processing procedure when adding the logical storage device 1540.

When adding the logical storage device 1540, the maintenance staff inputs the capacity to be added from the control terminal 1700.
The disk array control device 1300 has a control terminal 1700.
Accepts a request to add a logical storage device from.

The address management unit 1320 accepts a request to add a logical storage device and confirms the request contents (S2).
01). The address management unit 1320 refers to the physical / virtual storage correspondence table 140 and confirms whether there is an unused area in the virtual storage device 1530 (S202). If there is no unused area in any of the virtual storage devices 1530, the logical storage devices are assigned to all the virtual storage regions, and the logical storage device cannot be created in the disk array system any more, so the processing ends.

If there is an unused area of any virtual storage device, the address management unit 1320 compares the capacity of the logical storage device to be added with the total capacity of the unused areas of the virtual storage device (S203). If the added capacity is larger than the unused capacity, the requested capacity cannot be added, and the process ends.

If there is an unused area corresponding to the expanded capacity in any of the virtual storage devices 1530, the emulation type corresponding to the host connecting the requested capacity is set, and a new logical address is allocated to the logical storage. Device 15
40 is created (S204). When the logical storage device 1540 is newly set, each information in the storage configuration information 1400 is updated (S205).

Then, it is confirmed whether the logical storage device 1530 has been added by the requested capacity (S206).

FIG. 10 shows a processing procedure when the logical storage device 1540 is removed.

When the logical storage device 1540 is to be removed, the maintenance personnel inputs the capacity to be removed from the control terminal 1700.
The disk array device 1300 receives a request for removing the logical storage device 1540 from the control terminal 1700.

The address management unit 1320 accepts the request to remove the logical storage device and confirms the request contents (S3).
01). The address management unit 1320 transmits a confirmation request for deleting the data in the logical storage device to the control terminal 1700, and confirms whether the data may be deleted (S302).
If the response from the control terminal 1700 indicates that data deletion is not permitted, this process ends. If data deletion is allowed,
The address management unit 1320 cancels the association between the logical storage device 1540 and the virtual storage device 1530 registered in the logical / virtual storage correspondence table 1410 (S30).
3). Then, the emulation of the virtual storage device 1530 allocated to the logical storage device 1540 to be deleted is canceled,
Data on the physical recording device 1510 is deleted (S30
4).

The above process is repeated until all the logical storage devices 1540 to be removed are deleted (S305).

When the physical storage device 1510 fails, the disk array system can be continuously used by replacing it with a new physical storage device. Here, the new physical storage device may have a larger capacity than the device before replacement. This situation will be described with reference to FIG.

Four disk devices (physical storage device) 15
There are 10 parity groups 1520.
Initially, this parity group was composed of four 3 GB disk devices, but three (disks # 1 to # 3) have already been exchanged for 10 GB (FIG. 13A). However, at this time, what is used as the disk array device is the shaded portion (each disk 3 GB) in the figure,
Disks 1 to 3 of 7 GB (A in the figure) are unused.

Here, consider a case where the disk # 4 is replaced with a disk of 10 GB (FIG. 13B). Disk # 4
If you replace the disk, the capacity of all disk devices will be 10GB.
Are available. As a result, the area A which has not been used in FIG. 13A can be used.

The processing procedure at this time shown in FIG. 11 will be described by taking the case of FIG. 13 as an example.

When the disk # 4 is replaced with the physical storage device 1510 of 3 GB to 10 GB, the optimum placement processing unit 1
The 310 confirms the capacity of the physical storage device 1510 of this parity group 1520, and updates the physical / virtual storage correspondence table 1420 and the parity group attribute information 1460 (S401). Specifically, the minimum capacity 6400
From 3 GB to 10 GB, parity group capacity 650
Update 0 to 40 GB. Further, the virtual storage address 4200 is assigned to the added area, and the used / unused classification is registered as “unused”.

Next, the optimum allocation processing unit 1310 reconfigures the data of the physical storage device 1510 that has been replaced by using the parity in the parity group (S402).

Here, the address management unit 1320 confirms whether the minimum capacity 6400 has been updated (S40).
3). When the minimum capacity 6400 is updated, FIG.
Processing for using the area A in (a) is performed. That is,
The address management unit 1320 registers 7 GB of the added disk # 4 in the logical / virtual storage correspondence table 1420. The address management unit 1320 allocates virtual storage device addresses to the area A that has not been used up to now and the added 7 GB area, and the logical / virtual storage correspondence table 14
20 and the virtual storage attribute table 1430 are updated (S404).

As a result, the space of the storage area that can be used by the virtual storage device can be expanded without changing the existing data area.

Next, FIG. 12 shows a processing procedure for the address management unit 1320 to secure a reserved area. The reserved area refers to a data relocation destination area used when data is optimally allocated, an area used temporarily during data relocation processing, or the like.

When securing the reserve volume, the maintenance staff inputs the required reserve area capacity and the emulation type from the control terminal 1700. The disk array device 1300 receives a reserve area creation request from the control terminal 1700.

The address management unit 1320 accepts a reserve area setting request (S501). The address management unit 1320 confirms the capacity and emulation type included in the reserved area setting request, refers to the physical / virtual storage correspondence table 1420, the logical storage attribute table 1440, and the like, and determines whether the virtual storage device 1540 corresponding to this is unused. It is confirmed whether there is an area (S502).

If there is an unused area, a reserved area is created in the virtual storage area (S511). In particular,
The address management unit 1320 registers the unused area as a reserved area. This allows the unused storage area to be used as a reserve.

If there is not enough unused area, the maintenance personnel is asked whether or not the physical storage area allocated to the logical storage device is to be used as the reserve volume area (S5).
03). If the physical storage area is not allocated, step S5
Proceed to 07. When allocating a physical storage area, the logical storage attribute table 1440 is referenced and the host side path 340
It is determined whether there is a logical storage device 1540 for which 0 is not set (S504).

If there is no logical storage device 1540 for which the host side path 3400 has not been set, the flow advances to step S507. When there is a logical storage device 1540 for which the host side path 3400 has not been set, further, the host side path 340
It is determined whether the logical storage device 1540 of which 0 is not set has an area equal to or larger than the requested reserve capacity (S
505).

If the required capacity cannot be secured, the process proceeds to step S507. When the required capacity can be secured, a reserve is created in the logical storage area (S506).

The above process is repeated until all the required reserve capacity is secured (S507).

According to the embodiment described above, the storage area can be provided to the user in units of logical storage areas. Furthermore, it is possible to add storage devices without forcing the user to install a large-capacity storage device at a time.

Further, in a new large-capacity physical storage device used as a substitute for the physical storage device, a storage area which has not been used conventionally can be used.

Further, the reserved area can be secured by using an area other than the area used as the data area, and the data rearrangement processing can be performed.

[0084]

According to the present invention, the unused portion of the physical storage device can be effectively utilized.

[Brief description of drawings]

FIG. 1 is a diagram showing an overall structure of a system using a disk array system according to an embodiment of the present invention.

FIG. 2 is a logical storage device 1540 provided to a user,
It is a figure which shows the relationship between the physical storage apparatus 1510 and the storage apparatus 1530 virtually comprised.

FIG. 3 is a diagram showing an example of a data structure of a logical / virtual memory correspondence table 1410.

FIG. 4 is a diagram showing an example of a data structure of a logical storage attribute table 1440.

FIG. 5 is a diagram showing an example of a data structure of a physical / virtual storage correspondence table 1420.

FIG. 6 is a diagram showing an example of a data structure of a virtual storage attribute table 1430.

FIG. 7 is a diagram showing an example of a data structure of a parity group attribute table 1460.

FIG. 8 is a flowchart showing a processing procedure for creating a logical storage device 1540.

FIG. 9 is a flowchart showing a processing procedure for adding a logical storage device 1540.

FIG. 10 is a flowchart showing a processing procedure for removing a logical storage device 1540.

FIG. 11 is a flowchart showing a processing procedure for increasing the number of logical storage devices 1540 provided by the parity group 1520.

FIG. 12 is a flowchart showing a processing procedure for setting a reserve area.

FIG. 13 is a diagram for explaining a usage area before and after replacement of the physical storage device 1510;

[Explanation of symbols]

1000 ... host 1200 ... Disk array system 1300 ... Disk array control device 1310 ... Optimal placement processing unit 1320 ... Optimal data placement means 1400 ... Configuration information storage unit 1410 ... Logical / virtual memory correspondence table 1420 ... Physical / virtual memory correspondence table 1430 ... Virtual memory attribute table 1440 ... Logical storage attribute table 1460 ... Parity group attribute table 1500 ... Storage device 1510 ... Physical storage device 1520 ... Parity group 1530 ... Virtual storage device 1540 ... Logical storage device 1700 ... Control terminal 1800 ... I / O bus 1900 ... Network

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Takusei Iwamura             1099 Ozenji, Aso-ku, Kawasaki City, Kanagawa Prefecture             Ceremony company Hitachi Systems Development Laboratory (72) Inventor Koji Arai             2880 Kozu, Odawara City, Kanagawa Stock Association             Storage Systems Division, Hitachi, Ltd. F term (reference) 5B065 BA01 CA30 CC04 CC08 CE22                       EA13 EA23 PA08 ZA02                 5D044 AB01 BC01 CC05 CC09 DE03                       DE96

Claims (5)

[Claims] 1. A storage system comprising a plurality of parity groups including a plurality of storage devices, wherein any one of the plurality of storage devices in one parity group includes an unused area to which a logical address is not assigned, Of the multiple storage devices in the parity group of
A storage system including allocation means for allocating logical addresses to unused areas of all storage devices in the parity group up to the storage capacity of the storage device having the smallest capacity. 2. When any one of the plurality of storage devices in the one parity group is replaced, the storage capacity of the storage device having the smallest capacity is detected among the plurality of storage devices in the parity group after replacement. 3. The allocating means allocates logical addresses to the unused areas of all storage devices in the parity group up to the detected storage capacity.
The listed storage system. 3. A storage system comprising a plurality of parity groups including a plurality of storage devices, wherein any one of the plurality of storage devices in one parity group includes an unused area to which a logical address is not assigned, Of the plurality of storage devices in one parity group, up to the storage capacity of the storage device with the smallest capacity, unused areas of all storage devices in the parity group,
A storage system including means for performing processing for setting an area used for relocation processing. 4. An unused storage system comprising a plurality of parity groups including a plurality of storage devices, wherein some storage areas of any one of the plurality of storage devices in one parity group are not assigned a logical address. Registered as an area, among the plurality of storage devices in the one parity group,
A storage area management method for a storage system that allocates logical addresses to unused areas of all storage devices in the parity group up to the storage capacity of the storage device having the smallest capacity. 5. A process for configuring a storage system having a plurality of parity groups including a plurality of storage devices, and a logical address for a part of a storage area of one of the plurality of storage devices in one parity group. A process of registering as an unused area that is not allocated, and among the plurality of storage devices in the one parity group,
A program for causing a computer to execute processing of assigning logical addresses to unused areas of all storage devices in the parity group up to the storage capacity of the storage device having the smallest capacity.