Method of moving files in hierarchical storage system

Patent metadata

Field	Value
Publication number	US-2016124678-A1
Application number	US-201514821834-A
Country	US
Kind code	A1
Filing date	Aug 10, 2015
Priority date	Oct 31, 2014
Publication date	May 5, 2016
Grant date	—

Abstract

A method for moving files in a hierarchical storage system having a primary storage and a secondary storage including a sequential storage device from the primary storage to the secondary storage includes obtaining a predetermined file size to be written to the secondary storage, extracting, from a plurality of files in the primary storage, a file not stored in the secondary storage and having the oldest last access time, estimating a file size of the file having the oldest last access time on the secondary storage if the file having the oldest last access time is written to the secondary storage, and selecting the file having the oldest last access time as a file to be moved to the secondary storage as long as the estimated file size does not exceed the predetermined file size to be written to the secondary storage.

First claim

1 . A method for moving files in a hierarchical storage system having a primary storage and a secondary storage including a sequential storage device from the primary storage to the secondary storage, the method comprising the steps of:
obtaining a predetermined file size to be written to the secondary storage; extracting, from a plurality of files in the primary storage, a file not stored in the secondary storage and having an oldest last access time; estimating a file size of the file having the oldest last access time on the secondary storage if the file having the oldest last access time is written to the secondary storage; and selecting the file having the oldest last access time as a file to be moved to the secondary storage as long as the estimated file size does not exceed the predetermined file size to be written to the secondary storage.

2 . The method according to claim 1 , further comprising the step of:
repeating the extracting step to the selecting step until the predetermined file size is exceeded.

3 . The method according to claim 2 , further comprising the steps of:
moving files selected as files to be moved to the secondary storage to the secondary storage; and storing information in the primary storage as one file for indicating each file that is moved to the secondary storage.

4 . The method according to claim 3 , further comprising the step of:
writing the files that are moved to the secondary storage in an area identified as having the predetermined file size to be written to the secondary storage in the secondary storage in an ascending or descending order of file size.

5 . The method according to claim 1 , wherein the step of obtaining a predetermined file size to be written to the secondary storage includes the step of:
obtaining a predetermined file size to be sequentially written in one direction in the sequential storage device.

6 . The method according to claim 5 , further comprising the step of:
writing the files that are moved to the secondary storage in an area identified as having the predetermined file size to be sequentially written in the one direction in an ascending order of file size.

7 . The method according to claim 6 , further comprising the step of:
writing the files that are moved to the secondary storage in an area identified as having the predetermined file size to be sequentially written in a direction opposite to the one direction in a descending order of file size.

8 . The method according to claim 1 , wherein the sequential storage device is a tape drive, and the predetermined file size to be written to the secondary storage is a data size to be written on one wrap of a tape readable/writable in the tape drive.

9 . A computer program product for moving files in a hierarchical storage system, the computer program product comprising:
a computer readable non-transitory article of manufacture tangibly embodying computer readable instructions which, when executed, cause a computer to carry out a method comprising the steps of: obtaining a predetermined file size to be written to the secondary storage; extracting, from a plurality of files in the primary storage, a file not stored in the secondary storage and having an oldest last access time; estimating a file size of the file having the oldest last access time on the secondary storage if the file having the oldest last access time is written to the secondary storage; and selecting the file having the oldest last access time as a file to be moved to the secondary storage as long as the estimated file size does not exceed the predetermined file size to be written to the secondary storage.

10 . The computer program product according to claim 9 , further comprising the step of:
repeating the extracting step to the selecting step until the predetermined file size is exceeded.

11 . The computer program product according to claim 10 , further comprising the steps of:
moving files selected as files to be moved to the secondary storage to the secondary storage; and storing information in the primary storage as one file for indicating each file that is moved to the secondary storage.

12 . The computer program product according to claim 11 , further comprising the step of:
writing the files that are moved to the secondary storage in an area identified as having the predetermined file size to be written to the secondary storage in the secondary storage in an ascending or descending order of file size.

13 . The computer program product according to claim 9 , wherein the step of obtaining a predetermined file size to be written to the secondary storage includes the step of:
obtaining a predetermined file size to be sequentially written in one direction in the sequential storage device.

14 . The computer program product according to claim 13 , further comprising the step of:
writing the files that are moved to the secondary storage in an area identified as having the predetermined file size to be sequentially written in the one direction in an ascending order of file size.

15 . A method of moving files in a hierarchical storage system having a primary storage including at least one HDD and a secondary storage including at least one tape drive from the primary storage to the secondary storage, the method comprising the steps of:
obtaining, from the tape drive, a data size to be written on one wrap of a tape; extracting, from a plurality of files in the primary storage, a file not stored in the secondary storage and having an oldest last access time; estimating a file size of the file having the oldest last access time on the one wrap if the file having the oldest last access time is written to the tape in the tape drive; and selecting the file having the oldest last access time as a file to be moved to the tape drive as long as the estimated file size does not exceed the data size to be written on the one wrap.

16 . The method according to claim 15 , further comprising a step of repeating the extracting step to the selecting step until the data size to be written on the one wrap is exceeded.

17 . The method according to claim 16 , further comprising the steps of:
moving files selected as files to be moved to the tape drive to the tape drive; and storing information in the primary storage as one file for indicating each file that is moved to the tape drive.

18 . The method according to claim 17 , further comprising the step of:
writing the files that are moved to the tape drive on the one wrap of the tape in an ascending or descending order of file size.

19 . The method according to claim 17 , further comprising the step of:
writing the files that are moved to the tape drive on the one wrap of the tape in one direction in an ascending order of file size.

20 . The method according to claim 19 , further comprising the step of:
writing the files that are moved to the tape drive on the one wrap of the tape in a direction opposite to the one direction in a descending order of file size.

Assignees

• IBM

Inventors

• Hasegawa Tohru
• Iwanaga Masayuki
• Oishi Yutaka

Classifications

• G06F3/0685 Primary

  Hybrid storage combining heterogeneous device types, e.g. hierarchical storage, hybrid arrays · CPC title

• G06F3/0643 Primary

  Management of files · CPC title

• G06F3/0608

  Saving storage space on storage systems · CPC title

• G06F17/30221

  Physics · mapped topic

• G06F3/0647

  Migration mechanisms · CPC title