Virtual integrated cartridge loader for virtual tape storage system

• US 5,805,864 A
• Filed: 09/10/1996
• Issued: 09/08/1998
• Est. Priority Date: 09/10/1996
• Status: Expired due to Term

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Peake, Jonathan Wayne, Carlson, Wayne Charles, Fisher, James Arthur
• Primary Examiner(s): Teska, Kevin J.
• Assistant Examiner(s): KAZIMI, HANI M
• Application Number:
  US08/707,891
• Time in Patent Office: 728 Days
• Field of Search: 395/500, 395/82, 395/182.04, 395/821, 395/839, 395/860, 395/888, 360/92, 360/93, 360/132, 711/111, 711/4, 711/114, 711/118, 711/202, 711/209, 364/478.06, 364/478.03, 369/30, 369/34, 369/36, 369/47
• US Class Current: 703/24
• CPC Class Codes: G06F 3/0607 by facilitating the process of upgrading existing storage systems, e.g. for improving compatibility between host and storage device
• CPC Class Codes: G06F 3/0664 at device level, e.g. emulation of a storage device or system
• CPC Class Codes: G06F 3/0686 Libraries, e.g. tape libraries, jukebox
• CPC Class Codes: G11B 20/10 Digital recording or reproducing
• CPC Class Codes: Y10S 707/99953 Recoverability
• CPC Class Codes: Y10S 707/99956 File allocation

Abstract

Virtual data storage cartridges are created on a data storage subsystem to/from which volume writes and reads are directed. When a number of data volumes have been written, the controller may migrate them to the tape drive, a much faster process than writing directly to tape and enabling multiple logical volumes to be written to a single physical tape. With the present invention, virtual scratch cartridges are virtually premounted in a virtual drive loader while the virtual drive is accessing another virtual cartridge. When the host calls for a new scratch cartridge, it can be mounted in the virtual drive almost immediately, having already been virtually pre-loaded.

Claims

1. In a data storage system that provides an interface between a host and a data storage device ("DSD"), said interface emulating a virtual cartridge data storage library in communicating with the host, said virtual cartridge data storage library including a plurality of virtual cartridges, a method for virtually pre-loading virtual cartridges comprising the steps of:

maintaining an available cartridge database containing a list of virtual cartridges, each virtual cartridge identified in the available cartridge database by a virtual cartridge identifier;

maintaining an active cartridge map cross-referencing each item of data stored on the DSD with one of the virtual cartridges;

selecting a virtual cartridge identifier from the available database;

entering the selected virtual cartridge identifier in a pre-load map;

receiving from a host a scratch mount request; and

satisfying the scratch mount request by performing steps comprising;

choosing one of the cartridge identifiers from the pre-load map; and

removing the chosen virtual cartridge identifier from the pre-load map.

2. The method of claim 1, further comprising the steps of:

receiving from the host write data corresponding to the scratch mount request;

storing the write data in the DSD; and

updating the active cartridge map to cross-reference the write data with the chosen virtual cartridge.

3. The method of claim 1, the virtual cartridges representing magnetic tape cartridges.

4. The method of claim 1, the virtual cartridges representing optical media cartridges.

5. The method of claim 1, the step of selecting a virtual cartridge identifier from the available database comprising the steps of:

designating one of the virtual cartridges in the available cartridge database as being next; and

selecting the next virtual cartridge.

6. The method of claim 1, the DSD comprising at least one magnetic data storage drive.

15. The method of claim 1, each data format representing a different data storage pattern provided by virtual cartridges having that data format.

7. In a data storage system that provides an interface between a host and a cache, said interface emulating a virtual cartridge data storage library in communicating with the host, said virtual cartridge data storage library including a plurality of virtual cartridges, a method for virtually pre-loading virtual cartridges comprising the steps of:

maintaining an available cartridge database containing a list of virtual cartridges, each virtual cartridge identified in the available cartridge database by a virtual cartridge identifier;

maintaining an active cartridge map cross-referencing each item of data stored on the cache with one of the virtual cartridges;

selecting a virtual cartridge identifier from the available database;

entering the selected virtual cartridge identifier in a pre-load map;

receiving from a host a scratch mount request; and

satisfying the scratch mount request by performing steps comprising;

choosing one of the cartridge identifiers from the pre-load map; and

removing the chosen virtual cartridge identifier from the pre-load map.

8. The method of claim 7, further comprising the steps of:

receiving from the host write data corresponding to the scratch mount request;

storing the write data in the cache; and

updating the active cartridge map to cross-reference the write data with the chosen virtual cartridge.

9. The method of claim 7, the cache comprising a magnetic disk storage drive.

10. The method of claim 7, the cache comprising at least one solid state memory device.

11. In a data storage system that provides an interface between a host and a data storage device ("DSD"), said interface emulating a virtual cartridge data storage library in communicating with the host, said virtual cartridge data storage library including a plurality of virtual cartridges, said virtual cartridges having multiple different data formats, a method for virtually pre-loading virtual cartridges comprising the steps of:

maintaining an available cartridge database containing a list of virtual cartridges, each virtual cartridge identified in the available cartridge database by a virtual cartridge identifier;

maintaining an active cartridge map cross-referencing each item of data stored on the DSD with one of the virtual cartridges;

for each data format, selecting a virtual cartridge identifier of the corresponding data format from the available database and entering the selected virtual cartridge identifier in a pre-load map;

receiving from a host a scratch mount request for a virtual cartridge of a specified data format; and

satisfying the scratch mount request by performing steps comprising;

choosing from the pre-load map one of the cartridge identifiers having the specified data format; and

removing the chosen virtual cartridge identifier from the pre-load map.

12. The method of claim 11, further comprising the steps of:

receiving from the host write data corresponding to the scratch mount request;

storing the write data in the DSD; and

updating the active cartridge map to cross-reference the write data with the chosen virtual cartridge.

13. The method of claim 11, each data format representing a different data storage capacity.

14. The method of claim 11, each data format representing a different number of parallel data tracks provided by virtual cartridges having that data format.

16. The method of claim 11, the DSD comprising at least one magnetic data storage drive.

17. In a data storage system that provides an interface between a host and a data storage device ("DSD"), said interface emulating a virtual cartridge data storage library in communicating with the host, said virtual cartridge data storage library including a plurality of virtual cartridges, said library also including multiple virtual drives, a method for virtually pre-loading virtual cartridges comprising the steps of:

maintaining an available cartridge database containing a list of virtual cartridges, each virtual cartridge identified in the available cartridge database by a virtual cartridge identifier;

maintaining an active cartridge map cross-referencing each item of data stored on the DSD with one of the virtual cartridges;

for each virtual drive, performing steps comprising;

selecting a virtual cartridge identifier from the available database;

entering the selected virtual cartridge identifier in a pre-load map associated with that drive;

receiving from a host a scratch mount request and selection of one of the virtual drives to satisfy the mount request; and

satisfying the scratch mount request by performing steps comprising;

choosing one of the cartridge identifiers from the pre-load map associated with the selected virtual drive; and

removing the chosen virtual cartridge identifier from the pre-load map associated with the selected virtual drive.

18. The method of claim 17, further comprising the steps of:

receiving from the host write data corresponding to the scratch mount request;

storing the write data in the DSD; and

updating the active cartridge map to cross-reference the write data with the chosen virtual cartridge.

19. The method of claim 17, the DSD comprising at least one magnetic data storage drive.

20. An article of manufacture comprising a data storage medium tangibly embodying a program of machine-readable instructions executable by a digital processing apparatus to perform method steps for virtually pre-loading virtual cartridges in a data storage system that provides an interface between a host and a data storage device ("DSD"), said interface emulating a virtual cartridge data storage library in communicating with the host, said virtual cartridge data storage library including a plurality of virtual cartridges, said method steps comprising:

maintaining an available cartridge database containing a list of virtual cartridges, each virtual cartridge identified in the available cartridge database by a virtual cartridge identifier;

maintaining an active cartridge map cross-referencing each item of data stored on the DSD with one of the virtual cartridges;

selecting a virtual cartridge identifier from the available database;

entering the selected virtual cartridge identifier in a pre-load map;

receiving from a host a scratch mount request; and

satisfying the scratch mount request by performing steps comprising;

choosing one of the cartridge identifiers from the pre-load map; and

removing the chosen virtual cartridge identifier from the pre-load map.

21. The article of manufacture of claim 20, the method steps further comprising:

receiving from the host write data corresponding to the scratch mount request;

storing the write data in the DSD; and

updating the active cartridge map to cross-reference the write data with the chosen virtual cartridge.

22. The article of manufacture of claim 20, the virtual cartridges representing magnetic tape cartridges.

23. The article of manufacture of claim 20, the virtual cartridges representing optical media cartridges.

24. The article of manufacture of claim 20, the step of selecting a virtual cartridge identifier from the available database comprising the steps of:

designating one of the virtual cartridges in the available cartridge database as being next; and

selecting the next virtual cartridge.

25. An article of manufacture comprising a data storage medium tangibly embodying a program of machine-readable instructions executable by a digital processing apparatus to perform method steps for virtually pre-loading virtual cartridges in a data storage system that provides an interface between a host and a cache, said interface emulating a virtual cartridge data storage library in communicating with the host, said virtual cartridge data storage library including a plurality of virtual cartridges, said method steps comprising:

maintaining an available cartridge database containing a list of virtual cartridges, each virtual cartridge identified in the available cartridge database by a virtual cartridge identifier;

maintaining an active cartridge map cross-referencing each item of data stored on the cache with one of the virtual cartridges;

selecting a virtual cartridge identifier from the available database;

entering the selected virtual cartridge identifier in a pre-load map;

receiving from a host a scratch mount request; and

satisfying the scratch mount request by performing steps comprising;

choosing one of the cartridge identifiers from the pre-load map; and

removing the chosen virtual cartridge identifier from the pre-load map.

26. The article of manufacture of claim 25, the method steps further comprising:

receiving from the host write data corresponding to the scratch mount request;

storing the write data in the cache; and

updating the active cartridge map to cross-reference the write data with the chosen virtual cartridge.

27. The article of manufacture of claim 25, the cache comprising a magnetic disk storage drive.

28. The article of manufacture of claim 25, the cache comprising at least one solid state memory device.

29. An article of manufacture comprising a data storage medium tangibly embodying a program of machine-readable instructions executable by a digital processing apparatus to perform method steps for virtually pre-loading virtual cartridges in a data storage system that provides an interface between a host and a data storage device ("DSD"), said interface emulating a virtual cartridge data storage library in communicating with the host, said virtual cartridge data storage library including a plurality of virtual cartridges, said virtual cartridges having multiple different data formats, said method steps comprising:

maintaining an available cartridge database containing a list of virtual cartridges, each virtual cartridge identified in the available cartridge database by a virtual cartridge identifier;

maintaining an active cartridge map cross-referencing each item of data stored on the DSD with one of the virtual cartridges;

for each data format, selecting a virtual cartridge identifier of the corresponding data format from the available database and entering the selected virtual cartridge identifier in a pre-load map;

receiving from a host a scratch mount request for a virtual cartridge of a specified data format; and

satisfying the scratch mount request by performing steps comprising;

choosing from the pre-load map one of the cartridge identifiers having the specified data format; and

removing the chosen virtual cartridge identifier from the pre-load map.

30. The article of manufacture of claim 29, each data format representing a different data storage capacity.

31. The article of manufacture of claim 29, the method steps further comprising:

receiving from the host write data corresponding to the scratch mount request;

storing the write data in the DSD; and

updating the active cartridge map to cross-reference the write data with the chosen virtual cartridge.

32. The article of manufacture of claim 29, each data format representing a different number of parallel data tracks provided by virtual cartridges having that data format.

33. The article of manufacture of claim 29, each data format representing a different data storage pattern provided by virtual cartridges having that data format.

34. An article of manufacture comprising a data storage medium tangibly embodying a program of machine-readable instructions executable by a digital processing apparatus to perform method steps for virtually pre-loading virtual cartridges in a data storage system that provides an interface between a host and a data storage device ("DSD"), said interface emulating a virtual cartridge data storage library in communicating with the host, said virtual cartridge data storage library including a plurality of virtual cartridges, said library also including multiple virtual drives, said method steps comprising:

maintaining an available cartridge database containing a list of virtual cartridges, each virtual cartridge identified in the available cartridge database by a virtual cartridge identifier;

maintaining an active cartridge map cross-referencing each item of data stored on the DSD with one of the virtual cartridges;

for each virtual drive, performing steps comprising;

selecting a virtual cartridge identifier from the available database;

entering the selected virtual cartridge identifier in a pre-load map associated with that drive;

receiving from a host a scratch mount request and selection of one of the virtual drives to satisfy the mount request; and

satisfying the scratch mount request by performing steps comprising;

choosing one of the cartridge identifiers from the pre-load map associated with the selected virtual drive; and

removing the chosen virtual cartridge identifier from the pre-load map associated with the selected virtual drive.

35. The article of manufacture of claim 34, the method steps further comprising:

receiving from the host write data corresponding to the scratch mount request;

storing the write data in the DSD; and

updating the active cartridge map to cross-reference the write data with the chosen virtual cartridge.

36. A virtual cartridge data storage system, comprising:

a data storage device ("DSD");

an interface interposed between the DSD and a host, said interface emulating a virtual cartridge data storage library in communicating with the host, said virtual cartridge data storage library including a plurality of virtual cartridges, said interface being programmed to virtually pre-load virtual cartridges by performing steps comprising;

maintaining an available cartridge database containing a list of virtual cartridges, each virtual cartridge identified in the available cartridge database by a virtual cartridge identifier;

maintaining an active cartridge map cross-referencing each item of data stored on the DSD with one of the virtual cartridges;

selecting a virtual cartridge identifier from the available database;

entering the selected virtual cartridge identifier in a pre-load map;

receiving from a host a scratch mount request; and

satisfying the scratch mount request by performing steps comprising;

choosing one of the cartridge identifiers from the pre-load map; and

removing the chosen virtual cartridge identifier from the pre-load map.

37. The virtual cartridge data storage system of claim 36, the interface being further programmed to perform steps comprising:

receiving from the host write data corresponding to the scratch mount request;

storing the write data in the DSD; and

updating the active cartridge map to cross-reference the write data with the chosen virtual cartridge.

38. The apparatus of claim 36, further comprising a physical tape storage library coupled to the interface.

39. The apparatus of claim 36, the virtual cartridges representing magnetic tape cartridges.

40. The apparatus of claim 36, the virtual cartridges representing optical media cartridges.

41. The apparatus of claim 36, the step of selecting a virtual cartridge identifier from the available database comprising the steps of:

designating one of the virtual cartridges in the available cartridge database as being next; and

selecting the next virtual cartridge.

42. The apparatus of claim 36, the DSD comprising at least one magnetic data storage device.

43. The apparatus of claim 36, the DSD comprising random access memory.

44. A virtual cartridge data storage system, comprising:

a cache memory;

an interface interconnected between the cache and a host, said interface emulating a virtual cartridge data storage library in communicating with the host, said virtual cartridge data storage library including a plurality of virtual cartridges, said interface being programmed to virtually pre-load virtual cartridges by performing steps comprising;

maintaining an available cartridge database containing a list of virtual cartridges, each virtual cartridge identified in the available cartridge database by a virtual cartridge identifier;

maintaining an active cartridge map cross-referencing each item of data stored on the cache with one of the virtual cartridges;

selecting a virtual cartridge identifier from the available database;

entering the selected virtual cartridge identifier in a pre-load map;

receiving from a host a scratch mount request; and

satisfying the scratch mount request by performing steps comprising;

choosing one of the cartridge identifiers from the pre-load map; and

removing the chosen virtual cartridge identifier from the pre-load map.

45. The virtual cartridge data storage system of claim 44, the interface being further programmed to perform steps comprising:

receiving from the host write data corresponding to the scratch mount request;

storing the write data in the cache; and

updating the active cartridge map to cross-reference the write data with the chosen virtual cartridge.

46. The apparatus of claim 44, the cache comprising a magnetic disk storage drive.

47. The apparatus of claim 44, the cache comprising at least one solid state memory device.

48. A virtual cartridge data storage system, comprising:

a data storage device ("DSD");

an interface providing an interface between the DSD and a host, said interface emulating a virtual cartridge data storage library in communicating with the host, said virtual cartridge data storage library including a plurality of virtual cartridges, said virtual cartridges having multiple different data formats, said interface being programmed to virtually pre-load virtual cartridges by performing steps comprising;

maintaining an available cartridge database containing a list of virtual cartridges, each virtual cartridge identified in the available cartridge database by a virtual cartridge identifier;

maintaining an active cartridge map cross-referencing each item of data stored on the DSD with one of the virtual cartridges;

for each data format, selecting a virtual cartridge identifier of the corresponding data format from the available database and entering the selected virtual cartridge identifier in a pre-load map;

receiving from a host a scratch mount request for a virtual cartridge of a specified data format; and

satisfying the scratch mount request by performing steps comprising;

choosing from the pre-load map one of the cartridge identifiers having the specified data format; and

removing the chosen virtual cartridge identifier from the pre-load map.

49. The virtual cartridge data storage system of claim 48, the interface being further programmed to perform steps comprising:

receiving from the host write data corresponding to the scratch mount request;

storing the write data in the DSD; and

updating the active cartridge map to cross-reference the write data with the chosen virtual cartridge.

50. The apparatus of claim 48, each data format representing a different data storage capacity.

51. The apparatus of claim 48, each data format representing a different number of parallel data tracks provided by virtual cartridges having that data format.

52. The apparatus of claim 48, each data format representing a different data storage pattern provided by virtual cartridges having that data format.

53. The apparatus of claim 48, the DSD comprising at least one magnetic data storage device.

54. The apparatus of claim 48, the DSD comprising random access memory.

55. A virtual cartridge data storage system, comprising:

a data storage device ("DSD");

an interface coupled between a host and the DSD, said interface emulating a virtual cartridge data storage library in communicating with the host, said virtual cartridge data storage library including a plurality of virtual cartridges, said library also including multiple virtual drives, a method for virtually pre-loading virtual cartridges comprising the steps of;

maintaining an available cartridge database containing a list of virtual cartridges, each virtual cartridge identified in the available cartridge database by a virtual cartridge identifier;

maintaining an active cartridge map cross-referencing each item of data stored on the DSD with one of the virtual cartridges;

for each virtual drive, performing steps comprising;

selecting a virtual cartridge identifier from the available database;

entering the selected virtual cartridge identifier in a pre-load map associated with that drive;

receiving from a host a scratch mount request and selection of one of the virtual drives to satisfy the mount request; and

satisfying the scratch mount request by performing steps comprising;

choosing one of the cartridge identifiers from the pre-load map associated with the selected virtual drive; and

removing the chosen virtual cartridge identifier from the pre-load map associated with the selected virtual drive.

56. The virtual cartridge data storage system of claim 55, the interface being further programmed to perform steps comprising:

receiving from the host write data corresponding to the scratch mount request;

storing the write data in the DSD; and

updating the active cartridge map to cross-reference the write data with the chosen virtual cartridge.