Storage system and data storing method

Patent metadata

Field	Value
Publication number	US-2016019159-A1
Application number	US-201314773116-A
Country	US
Kind code	A1
Filing date	Oct 10, 2013
Priority date	Oct 10, 2013
Publication date	Jan 21, 2016
Grant date	—

Abstract

Provided is a storage system including: a storage medium including a plurality of physical storage areas having an upper limit number of rewrites, and a medium controller that controls I/O (input/output) of data to/from the plurality of physical storage areas; and a storage controller connected to the storage medium, wherein when any of the physical storage areas is not allocated to a write destination logical storage area among a plurality of logical storage areas, the medium controller allocates a vacant physical storage area among the plurality of physical storage areas to the write destination logical storage area and writes write target data to the allocated vacant physical storage area, and the plurality of logical storage areas includes an available logical area group determined based on a relationship between an available capacity of a logical storage capacity and a rewrite frequency of the plurality of physical storage areas.

First claim

1 . A storage system comprising:
a storage medium including a plurality of physical storage areas each having an upper limit number of rewrites, and a medium controller that controls I/O (input/output) of data to/from the plurality of physical storage areas; and a storage controller connected to the storage medium, wherein when data is erased from each physical storage area in order to rewrite data stored therein, the number of rewrites increases and the physical storage area is regarded as a vacant physical storage area, when any of the physical storage areas is not allocated to a write destination logical storage area among a plurality of logical storage areas or when a vacant area in which write target data can be stored is not present in a physical storage area allocated to the write destination logical storage area, the medium controller allocates a vacant physical storage area among the plurality of physical storage areas to the write destination logical storage area and writes the write target data to the allocated vacant physical storage area, the plurality of logical storage areas includes an available logical area group determined based on a relationship between an available capacity of a logical storage capacity and a rewrite frequency of the plurality of physical storage areas, the logical storage capacity is a total capacity of the plurality of logical storage areas, the available logical area group is one or more logical storage areas that can be used as the write destination logical storage area among the plurality of logical storage areas, and the available capacity is a capacity of an available logical area group which is one or more logical storage areas that can be used as the write destination logical storage area among the plurality of logical storage areas.

2 . The storage system according to claim 1 , wherein the storage controller provides a logical volume to an external apparatus, and receives a write request that designates an address of a write destination area in the logical volume,
a logical storage area corresponding to the write destination area within the available logical area group is the write destination logical storage area, and the available capacity when the logical volume has a high rewrite frequency is smaller than the available capacity when the logical volume has a low rewrite frequency.

3 . The storage system according to claim 1 , wherein the medium controller manages the plurality of logical storage areas and the available logical area group in correlation.

4 . The storage system according to claim 3 , wherein the storage controller transmits a setting command to the medium controller, and
the medium controller determines the available logical area group from the plurality of logical storage areas based on the setting command.

5 . The storage system according to claim 4 , wherein the setting command includes a proportion of the available capacity to the logical storage capacity, and the medium controller determines the available logical area group according to the proportion included in the setting command.

6 . The storage system according to claim 1 , wherein the storage controller provides a logical volume to an external apparatus, and receives a write request that designates an address of a write destination area in the logical volume,
a logical storage area corresponding to the write destination area within the available logical area group is the write destination logical storage area, the storage controller receives an input of a logical volume capacity desired by a user, and as the control, the storage controller: based on the relationship, calculates information on a maximum number of rewrites when the logical volume capacity desired by the user is used as the available capacity; and outputs the calculated information.

7 . The storage system according to claim 1 , further comprising a management computer that manages the storage controller, wherein
the storage controller provides a logical volume to an external apparatus, and receives a write request that designates an address of a write destination area in the logical volume, a logical storage area corresponding to the write destination area within the available logical area group is the write destination logical storage area, and the management computer: receives an input of a logical volume capacity desired by a user; based on the relationship, calculates information on a maximum number of rewrites when the logical volume capacity desired by the user is used as the available capacity; and outputs the calculated information.

8 . The storage system according to claim 1 , wherein the storage controller provides, to an external apparatus, a virtual volume which is a virtual logical volume configured according to Thin Provisioning and is formed of a plurality of virtual storage areas, and receives a write request that designates an address of a write destination virtual area in the virtual volume,
a logical storage area allocated to the write destination virtual area within the available logical area group is the write destination logical storage area, and the control involves decreasing the available capacity when allocating the logical storage area to a virtual volume having a high rewrite frequency.

9 . The storage system according to claim 8 , wherein the medium controller manages the plurality of logical storage areas and the available logical area group in correlation.

10 . The storage system according to claim 9 , wherein the storage controller transmits an allocation command to the medium controller, and
the medium controller determines the available logical area group from the plurality of logical storage areas based on the allocation command.

11 . The storage system according to claim 10 , wherein the allocation command includes information on a rewrite frequency of the virtual volume, and
the medium controller determines the available logical area group according to the information on the rewrite frequency included in the allocation command.

12 . A data storing method in a storage apparatus including: a storage medium including a plurality of physical storage areas each having an upper limit number of rewrites, and a medium controller that controls I/O (input/output) of data to/from the plurality of physical storage areas; and
a storage controller connected to the storage medium, the method comprising: when data is erased from each physical storage area in order to rewrite data stored therein, increasing the number of rewrites and regarding the physical storage area as a vacant physical storage area; and when any of the physical storage areas is not allocated to a write destination logical storage area among a plurality of logical storage areas or when a vacant area in which write target data can be stored is not present in a physical storage area allocated to the write destination logical storage area, allowing the medium controller to allocate a vacant physical storage area among the plurality of physical storage areas to the write destination logical storage area and write the write target data to the allocated vacant physical storage area, wherein the plurality of logical storage areas includes an available logical area group determined based on a relationship between an available capacity of a logical storage capacity and a rewrite frequency of the plurality of physical storage areas, the logical storage capacity is a total capacity of the plurality of logical storage areas, the available logical area group is one or more logical storage areas that can be used as the write destination logical storage area among the

Assignees

• Hitachi Ltd

Inventors

• Ueda Keisuke
• Uehara Go
• Ninose Kenta
• Hirayama Hiroshi

Classifications

• G06F12/0246 Primary

  in block erasable memory, e.g. flash memory · CPC title

• G06F12/10 Primary

  Address translation · CPC title

• G06F2212/65

  Details of virtual memory and virtual address translation · CPC title

• G06F3/0616

  in relation to life time, e.g. increasing Mean Time Between Failures [MTBF] · CPC title

• G06F3/0631

  by allocating resources to storage systems · CPC title