FILE INDEX, METADATA STORAGE, AND FILE SYSTEM MANAGEMENT FOR MAGNETIC TAPE

• US 20110238906A1
• Filed: 03/25/2010
• Published: 09/29/2011
• Est. Priority Date: 03/25/2010
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Richter, Rainer, Pease, David A., Amir, Arnon
• Granted Patent: US 9,063,666 B2
• Time in Patent Office: Days
• US Class Current: 711/111
• CPC Class Codes: G06F 12/0866 for peripheral storage systems, e.g. disk cache
• CPC Class Codes: G06F 16/2228 Indexing structures
• CPC Class Codes: G06F 2212/213 Tape storage
• CPC Class Codes: G06F 2212/224 Disk storage
• CPC Class Codes: G06F 2212/463 File
• CPC Class Codes: G06F 3/0611 in relation to response time
• CPC Class Codes: G06F 3/0617 in relation to availability
• CPC Class Codes: G06F 3/0643 Management of files
• CPC Class Codes: G06F 3/0686 Libraries, e.g. tape libraries, jukebox
• CPC Class Codes: G11B 20/1201 on tapes
• CPC Class Codes: G11B 2220/956 Linear tape open [LTO] format
• CPC Class Codes: G11B 27/002 Programmed access in sequence to a plurality of record carriers or indexed parts, e.g. tracks, thereof, e.g. for editing; transfer of record carriers from magazine G11B15/68, G11B17/10; G11B17/22
• CPC Class Codes: G11B 27/328 on a tape [TTOC]

Abstract

In one embodiment, a method includes loading a tape cartridge into at least one tape drive installed in an automated tape library, where a tape of the tape cartridge has at least two partitions; writing plurality of data blocks on a first of the partitions; and writing an index on a second of the partitions, wherein the index includes information about at least one of files and the blocks on the first partition

Claims

1. A method, comprising:

loading a tape cartridge into at least one tape drive installed in an automated tape library, wherein a tape of the tape cartridge has at least two partitions;

writing a plurality of data blocks on a first of the partitions; and

writing an index on a second of the partitions, wherein the index includes information about at least one of files and the blocks on the first partition.

2. The method of claim 1, wherein the automated tape library is mounted and presented as a mount point in a file system.

3. The method of claim 2, wherein the tape is represented by at least one of a directory and a name space under the mount point.

4. The method of claim 3, wherein directories and files on the tape are shown under the at least one of the directory and the name space corresponding to the tape and are listed hierarchically under the mount point.

5. The method of claim 2, further comprising showing the content of a plurality of tapes under at least one of a single directory and a name space as one combined volume.

6. The method of claim 2, further comprising allowing a search for at least one of files and directories using a search criterion selected from the group consisting of name, date, attributes and extended attributes.

7. The method of claim 2, further comprising receiving a request to open a file, wherein the file is opened by:

locating a tape cartridge containing a target of the file open request;

if cartridge is not already loaded in a drive, identifying an available tape drive in the library or making one available by unloading the tape drive;

issuing a load request for the tape cartridge into the tape drive;

reading an index from the tape cartridge into an in-memory data structure of the file system; and

opening an object in the index corresponding to the file and marking the object open in the in-memory data structure of the file system.

8. The method of claim 1, wherein information gathered from the index and metadata stored on the second partition of the cartridge is at least one of cached and saved on at least one of a computer and a non volatile storage.

9. The method of claim 8, wherein a unified index of contents of a plurality of tape cartridges stored in the automated tape library is created by:

obtaining a list of a plurality of tapes to be indexed;

sending a command to the automated tape library to load a selected tape into a tape drive;

reading index information from the tape;

appending information from the index to a unified index;

unloading the tape; and

repeating the loading, reading, appending, and unloading for each of the plurality of tape cartridges.

10. The method of claim 9, wherein a list of at least one of the tape cartridges and tapes thereof is obtained from an inventory request issued to the automated tape library.

11. The method of claim 9, further comprising loading tape cartridges imported into the automated library by an operator and appending information therefrom to the unified index.

12. The method of claim 9, further comprising allowing export of the indexed tape cartridges from the automated tape library while keeping the indexed tape cartridges index content in the unified index and providing browsing and search of file names, directories and attributes in the unified index while tape cartridges are not present in the automated tape library.

13. A system comprising:

a data tape cartridge, the data tape cartridge comprising;

a magnetic recording tape having at least two independently writable partitions, wherein the at least two independently writable partitions allow a plurality of files to be recorded in a first partition and an index to be recorded in a second partition, wherein the index contains references to the plurality of files in the first partition.

14. The system of claim 13, further comprising a tape mounting unit for mounting the data tape cartridge as a storage volume, wherein the data tape cartridge is usable by a computer program running on an attached computing system.

15. The system of claim 13, further comprising a tape automation robot;

a plurality of tape drives; and

a plurality of data tape cartridges.

16. The system of claim 15 further comprising hardware and/or file system software embodied on a computer readable medium for controlling the tape automation robot, mounting the plurality of data cartridges as a name space, and presenting at least some of the tape cartridges as an individual directory under the name space.

17. The system of claim 15, wherein the hardware and/or file system software controls the tape automation robot and the tape drives.

18. The system of claim 13, wherein the index further comprises a plurality of user settable file attributes.

19. The system of claim 13, wherein the index further contains a hierarchical directory and structure.

20. The system of claim 13, wherein the plurality of files are stored on more than one partition.

21. The system of claim 13, wherein use of data on the data tape cartridge is indistinguishable from use of data on disk.

22. A dual-partition tape cartridge, comprising:

a magnetic recording tape having a first partition and a second partition; and

an initial index written to the second partition, wherein the partitions are physically separate and independently addressable on the tape.

23. The dual-partition tape cartridge of claim 22, wherein a plurality of copies of the initial index are written in the second partition.

24. A computer program product for writing an index on a tape, the computer program product comprising:

a computer readable storage medium having computer readable program code embodied therewith, the computer readable program code comprising;

computer readable program code configured to load a tape cartridge into at least one tape drive installed in an automated tape library, where a tape of the tape cartridge has at least two partitions;

computer readable program code configured to write a plurality of data blocks on a first of the partitions; and

computer readable program code configured to write an index on a second of the partitions, wherein the index includes information about at least one of files and the blocks on the first partition.

25. A method, comprising:

loading a tape cartridge into a tape drive installed in an automated tape library, where a tape of the tape cartridge has at least two partitions;

reading an index from a first partition of the tape, wherein the index includes information about at least one of files and the blocks on a second partition of the tape; and

using the information to locate and read a plurality of data blocks of at least one file from the second partition.