Management system and management method for managing data units constituting schemas of a database

Patent metadata

Field	Value
Publication number	US-9870152-B2
Application number	US-201214404963-A
Country	US
Kind code	B2
Filing date	Jun 7, 2012
Priority date	Jun 7, 2012
Publication date	Jan 16, 2018
Grant date	Jan 16, 2018

Abstract

A management system manages a plurality of data units constituting schemas of a database in a storage device, which includes a plurality of first storage device sets having a plurality of storage areas. An ordered schema constituted of the plurality of data units having order properties defining respective orders is included in the schemas. When a second storage device set, which is a set of one or more second storage devices and in which each of the storage areas is a free storage area, is added to the first storage device set, the management system migrates two or more data units not consecutive in the order among a plurality of data units stored in the plurality of storage areas in the first storage device set respectively from at least the one first storage device set to the free storage areas of the second storage device set.

First claim

The invention claimed is:

1. A management system that manages a plurality of data units constituting one or more schemas of a database in a storage apparatus, the management system comprising:
storage resources; and
a control device coupled to the storage resources,
wherein the storage apparatus includes a plurality of first storage device sets having a plurality of storage areas,
wherein an ordered schema constituted of the plurality of data units having order properties defining respective orders is included in the one or more schemas,
wherein the storage resources store management information including mapping information as information indicating which data unit constituting the ordered schema is stored in which storage area and order information indicating the order of the data units,
wherein the first storage device set is a set of one or more first storage devices, and
wherein the control device is configured to
(A) migrate, when a second storage device set, which is a set of one or more second storage devices and in which each of the storage areas is a free storage area, is added to the first storage device set, two or more data units not consecutive in the order among the plurality of data units stored in the plurality of storage areas in the first storage device set respectively from at least the one first storage device set to the free storage areas of the second storage device set based on the management information, such that a plurality of the free storage areas is distributed over the first storage device sets and the second storage device set, and such that data units that are consecutive in order are stored in different storage device sets and no data units that are consecutive in order are stored in the same storage device set, without migrating data units between different first storage device sets.

2. The management system according to claim 1 ,
wherein the number of the first storage device sets is P (P is an integer equal to or larger than 2), each of the first storage devices includes Q storage areas (Q is an integer equal to or larger than 1), and therefore, the P first storage device sets include the (P ×Q) storage areas,
wherein the P data units consecutive in the order are stored in the P storage areas of the same row in the different first storage device sets in units of the P data units consecutive in the order, and
wherein the control device is configured to migrate the X-th oldest data unit (X is an integer and X=0, 1, . . . , (Q−1)) of the X-th first storage device set from the storage area of the X-th first storage device set to the free storage area of the second storage device set in (A).

3. The management system according to claim 2 ,
wherein, after (A), when the free storage area produced in the X-th first storage device set is not adjacent to the storage area storing a latest data unit in the X-th first storage device set, the control device is configured to migrate a second newest data unit in the X-th first storage device set from the storage area storing the second newest data unit to the free storage area in the X-th first storage device set.

4. The management system according to claim 2 ,
wherein, in (A), the control device is configured to terminate (A) after repeating migration of the data units from the first storage device set to the second storage device set Y times (Y is a natural number) and
wherein a value of the Y is equal to or less than the number of the storage areas possessed by the second storage device set.

5. The management system according to claim 1 ,
wherein the control device is configured to
migrate, when there are the plurality of first storage device sets, as many the data units as the first storage device sets from the respective first storage device sets to the second storage device set.

6. The management system according to claim 5 ,
wherein the control device is configured to
migrate, when there are the plurality of first storage device sets, the same number of the data units from the respective first storage device sets to the second storage device set by sequentially switching the first storage device set from which to select the data unit to be migrated to the second storage device set.

7. The management system according to claim 6 ,
wherein the control device is configured to
migrate, when there are the plurality of first storage device sets, the data units the orders of which are relatively apart from the respective first storage device sets to the second storage device set.

8. The management system according to claim 7 ,
wherein the control device is configured to
make ranking of the order in the first storage device sets of the data unit, migrated to the second storage device set, different between the different first storage device sets.

9. The management system according to claim 1 ,
wherein the control device is configured to
(B) cause addition of a new storage area capable of storing the data unit of the ordered schema when determination is made that free areas of the storage areas capable of storing the data unit of the ordered schema in the first storage device set are equal to or less than a predetermined amount, determine whether the new storage area added is the storage area of the second storage device set, and perform (A) when the new storage area is the storage area of the second storage device set.

10. The management system according to claim 9 ,
wherein the control device is configured to
determine whether the addition of a new data unit to the schema of the database has occurred,
perform (B) when the addition of the data unit has occurred, and
store the new data unit in the free area after performing (A) so that the data units that are consecutive can be stored in different storage device sets.

11. The management system according to claim 1 ,
wherein the control device is configured to, after performing (A),
(C) migrate, when the free area and the storage area in which a latest data unit in the first storage device set containing the free area are not present within a predetermined range, the data unit within the predetermined range to the free area.

12. The management system according to claim 11 ,
wherein the control device has the predetermined range in (C) described above as a range adjacent to the free area.

13. The management system according to claim 11 ,
wherein the control device is configured to store the new data units in the free areas after performing (C), so that a plurality of new data units in the first storage device set can be stored in a relatively limited range of the first storage device set.

14. The management system according to claim 1 ,
wherein, in (A), the control device is configured to migrate one or more data units within the same first storage device set for at least one of the plurality of first storage device sets, in addition to migrating the two or more data units not consecutive in the order to the free storage areas of the second storage device set based on the management information, such that data units that are consecutive in order are stored in different storage device sets and no data units that are consecutive in order are stored in the same storage device set, without migrating data units between different first storage device sets.

15. A non-transitory computer readable storage medium storing a computer program that causes a computer to manage a plurality of data units constituting one or more schemas of a database in a storage apparatus,
wherein the storage apparatus includes a plurality of first storage device sets having a

Assignees

• Idei Hideomi
• Nishikawa Norifumi
• Fujiwara Shinji
• Mogi Kazuhiko
• Hitachi Ltd

Inventors

• Idei Hideomi
• Nishikawa Norifumi
• Fujiwara Shinji
• Mogi Kazuhiko

Classifications

• G06F3/067

  Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS] · CPC title

• G06F3/061 Primary

  Improving I/O performance · CPC title

• G06F3/0665

  at area level, e.g. provisioning of virtual or logical volumes · CPC title

• G06F3/0689

  Disk arrays, e.g. RAID, JBOD · CPC title

• G06F3/0647

  Migration mechanisms · CPC title