Method and system for managing data and users of data in a data processing system

• US 5,465,359 A
• Filed: 11/01/1993
• Issued: 11/07/1995
• Est. Priority Date: 11/01/1993
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Surman, David H., Pushong, Kelly B., Nick, Jeffrey M., Swanson, Michael D., Allen, Ruth A., Goetze, Lisa M.
• Primary Examiner(s): Heckler, Thomas M.
• Application Number:
  US08/146,727
• Time in Patent Office: 736 Days
• Field of Search: 395/650, 395/700
• US Class Current: 718/101
• CPC Class Codes: G06F 9/52 Program synchronisation; Mutual exclusion, e.g. by means of semaphores

Abstract

A method and system for managing information in a data processing system is provided. The data processing system includes one or more operating systems coupled to a coupling facility. Stored within the coupling facility is data, which is accessed by one or more users. The status of those users are also stored in the coupling facility. A number of operating system services are provided for recording the users'"'"' status and managing the data and the users of the data. The data may include cache, list and/or lock structures.

Claims

1. A method for managing status information in a data processing system comprising at least one operating system, said method comprising the steps of:

executing by said at least one operating system a user process, said at least one operating system being coupled to a coupling facility comprising processing means and a memory, said memory comprising a storage structure; and

maintaining at said coupling facility status information indicating whether said user process is attached to said storage structure.

2. The method of claim 1, wherein said storage structure comprises one or more objects, each of said one or more objects having one or more controls for indicating an interest of said user process in said one or more objects.

3. The method of claim 2, further comprising the step of modifying said status information and said one or more controls in a single atomic operation.

4. The method of claim 3, wherein said single atomic operation comprises a detach command, said detach command updating said one or more controls, resetting a user control corresponding to said user process of said storage structure, and updating said status information of said user process.

5. The method of claim 4, wherein said storage structure is a cache structure and said one or more controls are located within said cache structure within said coupling facility and said user process is identified by a local cache identifier.

6. The method of claim 5, wherein said local cache identifier is stored within said coupling facility.

7. The method of claim 5, wherein said one or more controls are stored within a directory register located within said cache structure.

8. The method of claim 5, wherein said status information is stored within a local-cache control block located within said cache structure.

9. The method of claim 4, wherein said storage structure is a list structure and said one or more controls are located within said list structure within said coupling facility and said user is identified by a user identifier.

10. The method of claim 9, wherein said user identifier is stored within said coupling facility.

11. The method of claim 9, wherein said one or more controls are stored within a list monitor table located within said list structure.

12. The method of claim 9, wherein said status information is stored within a list-user control block located within said list structure.

13. The method of claim 2, further comprising the step of updating said one or more controls when said user process terminates due to an unexpected condition.

14. The method of claim 13, further comprising the step of maintaining allocation of said storage structure and said status information when said user process terminates due to an unexpected condition until one or more predefined conditions occur.

15. The method of claim 14, wherein one or more user processes in addition to the user process terminated due to an unexpected condition (abnormally terminated user process) is connected to said storage structure, and wherein said one or more predefined conditions include providing by each of said one or more user processes an event exit response.

16. The method of claim 15, further comprising the step of performing one of having said abnormally terminated user process reconnect to said storage structure, having a peer connection inform said data processing system that said storage structure and said abnormally terminated user process no longer need to be allocated, and unconditionally deleting said status information of said abnormally terminated user process.

17. The method of claim 14, wherein said one or more predefined conditions include said user process reconnecting to said storage structure.

18. The method of claim 14, wherein said one or more predefined conditions includes unconditionally deleting said status information.

19. The method of claim 2, further comprising the step of updating said one or more controls when said user process is terminated.

20. The method of claim 19, further comprising the step of determining whether said user process is terminated due to an expected condition or an unexpected condition.

21. The method of claim 19, further comprising specifying at a connection of said user process to said storage structure whether said status information is to be maintained when said termination is due to an unexpected condition.

22. The method of claim 19, wherein said termination is performed by a disconnect service, said disconnect service providing the ability to indicate a reason for said termination.

23. The method of claim 19, further comprising the step of updating said one or more controls when said user process terminates due to an expected condition.

24. The method of claim 1, wherein said maintaining step comprises the step of maintaining at said coupling facility status information for a plurality of user processes.

25. The method of claim 24, further comprising the step of notifying one or more of said plurality of user processes which is active when one of said plurality of user processes terminates.

26. The method of claim 25, further comprising the step of performing cleanup for said terminated user process subsequent to receiving a response from one or more of said plurality of user processes.

27. The method of claim 26, wherein said cleanup comprises modifying one or more controls corresponding to said terminated user process, resetting a user control corresponding to said terminated user processes, and updating said status information of said terminated user process.

28. The method of claim 25, further comprising the step of performing cleanup for said terminated user process subsequent to receiving a response from all of said plurality of user processes.

29. The method of claim 1, further comprising the step of terminating said storage structure when said user process is terminated.

30. The method of claim 29, further comprising the step of conditionally keeping said storage structure when said user process is terminated.

31. The method of claim 30, wherein said conditionally keeping step is dependent on whether said user process is terminated due to an expected condition or an unexpected condition.

32. The method of claim 1, further comprising the step of connecting said user process to said storage structure.

33. The method of claim 32, further comprising the step of disconnecting said user process from said storage structure.

34. The method of claim 1, further comprising the step of conditionally keeping said status information when said user process is terminated.

35. The method of claim 34, wherein said conditionally keeping step is dependent upon whether said user process terminates due to an expected condition or an unexpected condition.

36. The method of claim 1, further comprising the step of maintaining allocation of said storage structure when said user process is terminated.

37. The method of claim 1, wherein said data processing system comprises a plurality of operating systems and said data processing system further comprises the step of modifying one or more controls of said storage structure, resetting a user control corresponding to said user process regardless of the operating system said user process is active on, and updating said status information of said user process.

38. A system for managing status information in a data processing system comprising at least one operating system for executing a user process, said system comprising:

a coupling facility coupled to said at least one operating system, said coupling facility comprising a processing means and a memory, said memory comprising a storage structure; and

means for maintaining at said coupling facility status information indicating whether said user process is attached to said storage structure.

39. The system of claim 38, wherein said storage structure comprises one or more objects, each of said one or more objects having one or more controls for indicating an interest of said user process in said one or more objects.

40. The system of claim 39, further comprising means for modifying said status information and said one or more controls in a single atomic operation.

41. The system of claim 40, wherein said single atomic operation comprises detach means, said detach means comprising means for updating said one or more controls, means for resetting a user control corresponding to said user process, and means for updating said status information of said user process.

42. The system of claim 41, wherein said storage structure is a cache structure and said one or more controls are located within said cache structure within said coupling facility and said user process is identified by a local cache identifier.

43. The system of claim 42, wherein said local cache identifier is stored within said coupling facility.

44. The system of claim 42, wherein said one or more controls are stored within a directory register located within said cache structure.

45. The system of claim 42, wherein said status information is stored within a local-cache control block located within said cache structure.

46. The system of claim 41, wherein said storage structure is a list structure and said one or more controls are located within said list structure within said coupling facility and said user is identified by a user identifier.

47. The system of claim 46, wherein said user identifier is stored within said coupling facility.

48. The system of claim 46, wherein said one or more controls are stored within a list monitor table located within said list structure.

49. The system of claim 46, wherein said status information is stored within a list-user control block located within said list structure.

50. The system of claim 39, further comprising means for updating said one or more controls when said user process terminates due to an unexpected condition.

51. The system of claim 50, further comprising means for maintaining allocation of said storage structure and said status information when said user process terminates due to an unexpected condition until one or more predefined conditions occur.

52. The system of claim 51, wherein said one or more predefined conditions include means for said user process to reconnect to said storage structure.

53. The system of claim 51, wherein said one or more predefined conditions include means for unconditionally deleting said status information.

54. The system of claim 51, wherein one or more user processes in addition to the user process terminated due to an unexpected condition (abnormally terminated) is connected to said storage structure, and wherein said one or more predefined conditions include means for providing by each of said one or more user processes an event exit response.

55. The system of claim 39, further comprising means for updating said one or more controls when said user process is terminated.

56. The system of claim 55, further comprising means for determining whether said user process is terminated due to an expected condition or an unexpected condition.

57. The system of claim 55, further comprising means for specifying at a connection of said user process to said storage structure whether said status information is to be maintained when said termination is due to an unexpected condition.

58. The system of claim 55, wherein said termination is performed by a disconnect means, said disconnect means providing the ability to indicate a reason for said termination.

59. The system of claim 55, further comprising means for updating said one or more controls when said user process terminates due to an expected condition.

60. The system of claim 38, wherein said maintaining means comprises means for maintaining at said coupling facility status information for a plurality of user processes.

61. The system of claim 60, further comprising means for notifying one or more of said plurality of user processes which is active when one of said plurality of user processes terminates.

62. The system of claim 61, further comprising cleanup means for cleaning up said terminated user process subsequent to receiving a response from one or more of said plurality of user processes.

63. The system of claim 62, further comprising cleanup means for cleaning up said terminated user process subsequent to receiving a response from all of said plurality of user processes.

64. The system of claim 62, wherein said cleanup means comprises means for modifying one or more controls corresponding to said terminated user process, means for resetting a user control corresponding to said terminated user process, and means for updating said status information of said terminated user process.

65. The system of claim 38, further comprising means for terminating said storage structure when said user process is terminated.

66. The system of claim 65, further comprising means for conditionally keeping said storage structure to be terminated when said user process is terminated.

67. The system of claim 66, wherein said conditionally keeping means comprises means for determining whether said user process is terminated due to an expected condition or an unexpected condition.

68. The system of claim 38, further comprising connect means for connecting said user process to said storage structure.

69. The system of claim 68, further comprising disconnecting means for disconnecting said user process from said storage structure.

70. The system of claim 38, further comprising means for conditionally keeping said status information when said user process is terminated.

71. The system of claim 70, wherein said conditionally keeping means comprises means for determining whether said user process terminates due to an expected or unexpected condition.

72. The system of claim 38, further comprising means for maintaining allocation of said storage structure when said user process is terminated.

73. The system of claim 38, wherein said data processing system comprises a plurality of operating systems and said data processing system further comprises means for modifying one or more controls of said storage structure, means for resetting a user control corresponding to said user process regardless of the operating system said user process is active on, and means for updating said status information of said user process.

74. A computer system comprising:

at least one operating system executing a user process; and

a coupling facility coupled to said at least one operating system, said coupling facility comprising processing means and a storage structure, said storage structure comprising status information indicating whether said user process is attached to said storage structure.

75. The computer system of claim 74, wherein said storage structure is one of a cache structure and a list structure.