SYSTEM AND METHOD FOR OPTIMIZED RECLAMATION PROCESSING IN A VIRTUAL TAPE LIBRARY SYSTEM

• US 20120265954A1
• Filed: 08/30/2010
• Published: 10/18/2012
• Est. Priority Date: 11/27/2009
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Haustein, Nils, Neff, Stefan
• Granted Patent: US 9,009,443 B2
• Time in Patent Office: Days
• US Class Current: 711/160
• CPC Class Codes: G06F 3/061 Improving I/O performance
• CPC Class Codes: G06F 3/0629 Configuration or reconfiguration of storage systems
• CPC Class Codes: G06F 3/0664 at device level, e.g. emulation of a storage device or system
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]
• CPC Class Codes: G06F 3/0686 Libraries, e.g. tape libraries, jukebox
• CPC Class Codes: G06F 3/0689 Disk arrays, e.g. RAID, JBOD

Abstract

A storage management application determines that a source virtual tape requires reclamation, identifies all block addresses for active data of a source virtual tape and sorts the block addresses in an ascending order, identifies a target virtual tape which has sufficient free capacity to store the active data of said source virtual tape and the last written block address on said target virtual tape, and sends a command to the VTL-system instructing it to perform reclamation including information about said source and said target virtual tape, the sorted list of block addresses denoting active data on the source virtual tape and the starting block address on the target virtual tape. The reclamation logic references the active data host blocks of said source volume to said target virtual tape starting at said starting block address by just updating the host block to disk block mapping table.

Claims

1-7. -7. (canceled)

8. A method for managing virtual tapes in a virtual tape library system, comprising:

mapping each host block written by a storage management application to a respective disk block on a disk system of the virtual tape library system in a disk block to host block mapping table;

determining that a source virtual tape requires reclamation;

identifying block addresses for active data of the source virtual tape;

identifying a target virtual tape that has capacity to store the active data of the source virtual tape;

identifying a last written block address on the target virtual tape; and

mapping the active data of the source virtual tape to the target virtual tape starting at the last written block address on the target virtual tape by updating the disk block to host block mapping table.

9. The method of claim 8, further comprising:

sorting the block addresses for the active data of the source virtual tape in an ascending order.

10. The method of claim 8, wherein mapping the active data further comprises:

for the block addresses for the active data of the source virtual tape, updating the disk block to host block mapping table to add new block addresses of the target virtual tape.

11. The method of claim 8, further comprising:

removing the block addresses for the active data of the source virtual tape from the disk block to host block mapping table to free up space in the virtual tape library system.

12. The method of claim 8, further comprising:

updating an object mapping table by assigning the block addresses for the active data of the source virtual tape to new block addresses of the target virtual tape starting at the last written block address on the target virtual tape and deleting the block addresses for the active data for the source virtual tape.

13. The method of claim 8, further comprising:

identifying host blocks for inactive data of the source virtual tape; and

deleting the host blocks for the inactive data of the source virtual tape by;

verifying that the source virtual tape exists in the virtual tape library system;

verifying that the host blocks exist in the disk block to host block mapping table; and

deleting each block address for each of the host blocks in the disk block to host block mapping table.

14. The method of claim 8, wherein the disk block to host block mapping table has columns for a disk block, a host block, and a target virtual tape identifier.

15. The method of claim 8, further comprising:

storing an object mapping table, wherein the block addresses, the target virtual tape, and the last written block address are identified using the object mapping table.

16. The method of claim 8, wherein the storage management application sends a reclamation command including information about the source virtual tape, the target virtual tape, the active data of the source virtual tape, and the last written block address of the target virtual tape to the virtual tape library system, instructing the virtual tape library system to perform reclamation.

17. The method of claim 16, wherein the reclamation command comprises a SCSI mode select command with a mode page.

18. A computer program product for managing virtual tapes in a virtual tape library system, the computer program product comprising:

a computer readable medium including computer readable program code that, when executed by a processor of a computer, is configured to perform;

mapping each host block written by a storage management application to a respective disk block on a disk system of the virtual tape library system in a disk block to host block mapping table;

determining that a source virtual tape requires reclamation;

identifying block addresses for active data of the source virtual tape;

identifying a target virtual tape that has capacity to store the active data of the source virtual tape;

identifying a last written block address on the target virtual tape; and

mapping the active data of the source virtual tape to the target virtual tape starting at the last written block address on the target virtual tape by updating the disk block to host block mapping table.

19. The computer program product of claim 18, further comprising:

sorting the block addresses for the active data of the source virtual tape in an ascending order.

20. The computer program product of claim 18, wherein mapping the active data further comprises:

for the block addresses for the active data of the source virtual tape, updating the disk block to host block mapping table to add new block addresses of the target virtual tape.

21. The computer program product of claim 18, further comprising:

removing the block addresses for the active data of the source virtual tape from the disk block to host block mapping table to free up space in the virtual tape library system.

22. The computer program product of claim 18, further comprising:

updating an object mapping table by assigning the block addresses for the active data of the source virtual tape to new block addresses of the target virtual tape starting at the last written block address on the target virtual tape and deleting the block addresses for the active data for the source virtual tape.

23. An electronic data processing system for managing virtual tapes in a virtual tape library system, comprising:

a processor; and

memory elements coupled to the processor, wherein the memory elements store program code, and the program code is executed to perform operations, wherein the operations comprise;

mapping each host block written by a storage management application to a respective disk block on a disk system of the virtual tape library system in a disk block to host block mapping table;

determining that a source virtual tape requires reclamation;

identifying block addresses for active data of the source virtual tape;

identifying a target virtual tape that has capacity to store the active data of the source virtual tape;

identifying a last written block address on the target virtual tape; and

mapping the active data of the source virtual tape to the target virtual tape starting at the last written block address on the target virtual tape by updating the disk block to host block mapping table.

24. The electronic data processing system of claim 23, further comprising:

sorting the block addresses for the active data of the source virtual tape in an ascending order.

25. The electronic data processing system of claim 23, wherein mapping the active data further comprises:

for the block addresses for the active data of the source virtual tape, updating the disk block to host block mapping table to add new block addresses of the target virtual tape.

26. The electronic data processing system of claim 23, further comprising:

removing the block addresses for the active data of the source virtual tape from the disk block to host block mapping table to free up space in the virtual tape library system.

27. The electronic data processing system of claim 23, further comprising:

updating an object mapping table by assigning the block addresses for the active data of the source virtual tape to new block addresses of the target virtual tape starting at the last written block address on the target virtual tape and deleting the block addresses for the active data for the source virtual tape.