Metadata storing technique

Patent metadata

Field	Value
Publication number	US-2016147479-A1
Application number	US-201514919757-A
Country	US
Kind code	A1
Filing date	Oct 22, 2015
Priority date	Nov 26, 2014
Publication date	May 26, 2016
Grant date	—

Abstract

A computer-implemented metadata processing method and a system includes writing metadata to or reading metadata from a storage medium in which an index that contains metadata of each of one or more pieces of data is stored. The method and system include determining, in response to a processing request, which includes a write request or a read request, when to communicate with a storage area outside the index. At least a portion of content of the metadata relating to the processing request is processed, and accessed, including storing or obtaining, in the index, location information indicating the storage area of the portion of content of the metadata.

First claim

What is claimed is:

1 . A computer-implemented metadata processing method which includes writing metadata to or reading metadata from a storage medium in which an index that contains metadata of each of one or more pieces of data is stored, the method comprising:
determining using a computer, in response to a processing request, which includes a write request or a read request, when to communicate with a storage area outside the index; processing at least a portion of content of the metadata relating to the processing request to or from the storage area outside the index; and accessing, including storing or obtaining, in the index, location information indicating the storage area of the portion of content of the metadata.

2 . The method of claim 1 , further comprising:
determining, in response to the write request for writing metadata, when a capacity of the metadata relating to the write request meets a criterion of outside-index storage; writing at least a portion of content of the metadata relating to the write request to a storage area outside the index in a case where the capacity is determined to meet the criterion of outside-index storage; and storing, in the index, location information indicating the storage area to which the at least a portion of the content is written.

3 . The metadata writing method according to claim 2 , further comprising:
storing the content of the metadata relating to the write request in the index in a case where the capacity is determined to not meet the criterion of outside-index storage.

4 . The metadata writing method according to claim 2 , wherein,
the index is maintained on a storage device included in the computer system, and the metadata writing method further comprises overwriting an index section defined in the storage medium with a most recent version of the index.

5 . The metadata writing method according to claim 4 , wherein,
the writing to a storage area outside the index includes: instructing a storage medium driving device to write the at least a portion of the content to a data section that is defined in the storage medium separately from the index section, and obtaining, from the storage medium driving device, location information that indicates the storage area in the storage medium to which the at least a portion of the content is written.

6 . The metadata writing method according to claim 5 , wherein content of each of the one or more pieces of data and multiple versions of the index are additionally stored in the data section of the storage medium.

7 . The metadata writing method according to claim 2 , wherein the storage medium is a sequential access medium.

8 . The metadata writing method according to claim 2 , wherein the storage medium is a tape medium.

9 . The method of claim 1 , further comprising:
determining, in response to the read request for reading metadata, when the metadata relating to the read request is stored outside the index; obtaining, from the index, location information indicating a storage area outside the index in a case where the metadata is determined to be stored outside the index; and reading at least a portion of content of the metadata relating to the read request from the storage area identified by using the obtained location information.

10 . The method according to claim 9 , further comprising:
obtaining, from the index, the content of the metadata relating to the read request in a case where the metadata is determined to not be stored outside the index.

11 . The method according to claim 9 , further comprising:
reading a most recent version of the index from an index section defined in the storage medium, and maintaining the most recent version of the index on a storage device included in the computer system.

12 . The metadata reading method according to claim 11 , wherein,
the reading at least a portion of content of the metadata relating to the read request includes: instructing a storage medium driving device to perform reading by giving location information indicating the storage area in a data section that is defined in the storage medium separately from the index section, and obtaining a result of reading the at least a portion of the content from the storage medium driving device.

13 . The metadata reading method according to claim 9 , wherein,
the metadata stored outside the index is written to a data section of the storage medium because a capacity of the metadata meets a criterion of outside-index storage, and content of each of the one or more pieces of data and multiple versions of the index are additional stored in the data section of the storage medium.

14 . A file management system for performing, on a computer system, file management for a storage medium in which an index that contains metadata of each of one or more pieces of data is stored, the file management system comprising:
a storage determination unit that determines, in response to a processing request, which includes a write request or a read request, when to communicate with a storage area outside the index; a processing unit, including a writing unit or an obtaining unit, that processes at least a portion of content of the metadata relating to the processing request to or from the storage area outside the index; and an accessing unit, including a storing unit or a reading unit, that stores or reads, in the index, location information indicating the storage area of the portion of content of the metadata.

15 . The file management system of claim 14 , the file management system comprising:
a storage destination determination unit that determines, in response to the write request for writing metadata, when a capacity of the metadata relating to the write request meets a criterion of outside-index storage; the writing unit writes at least a portion of content of the metadata relating to the write request to a storage area outside the index when the capacity is determined to meet the criterion of outside-index storage; and the storing unit stores, in the index, location information indicating the storage area to which the at least a portion of the content is written.

16 . The file management system of claim 14 , the file management system comprising:
a storage source determination unit that determines, in response to the read request for reading metadata, whether the metadata relating to the read request is stored outside the index; the obtaining unit obtains, from the index, location information indicating a storage area outside the index in a case where the metadata is determined to be stored outside the index; and the reading unit reads at least a portion of content of the metadata relating to the read request from the storage area identified by using the obtained location information.

17 . A computer system comprising:
a processor; a memory with which the processor communicates; and an interface device used to make a connection with a storage medium driving device that drives a storage medium in which an index that contains metadata of each of one or more pieces of data is stored, wherein the processor being configured to: determine, in response to a processing request, which includes a write request or a read request, when to communicate with a storage area outside the index; process at least a portion of content of the metadata relating to the processing request to or from the storage area outside the index; and access, including storing or obtaining, in the index, location information indicating the storage area of the po

Assignees

• IBM

Inventors

• Iwanaga Masayuki
• Ohta Yumiko
• Oishi Yutaka

Classifications

• G06F16/134 Primary

  Distributed indices · CPC title

• G06F3/0686

  Libraries, e.g. tape libraries, jukebox · CPC title

• G06F3/0655

  Vertical data movement, i.e. input-output transfer; data movement between one or more hosts and one or more storage devices · CPC title

• G06F3/0643 Primary

  Management of files · CPC title

• G06F3/0665

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