Real composite objects for providing high availability of resources on networked systems

• US 7,475,127 B2
• Filed: 12/02/2002
• Issued: 01/06/2009
• Est. Priority Date: 11/30/2001
• Status: Active Grant

• Current Assignee: Oracle International Corporation (Oracle Corporation)
• Original Assignee: Oracle International Corporation (Oracle Corporation)
• Inventors: Brower, David, Colrain, Carol Lyndall, Creighton, Jonathan
• Primary Examiner(s): Vaughn, Jr.; William C.
• Assistant Examiner(s): Shingles; Kristie D
• Application Number:
  US10/308,918
• Publication Number:
  US 20030105866A1
• Time in Patent Office: 2,227 Days
• Field of Search: 709208-211, 709223-226, 709/229, 709/201, 709/248
• US Class Current: 709/223
• CPC Class Codes: G06F 2209/5011 Pool
• CPC Class Codes: G06F 2209/505 Clust
• CPC Class Codes: G06F 9/5061 Partitioning or combining of resources

Abstract

A composite resource is established that includes a plurality of members. Each of the members is capable of providing a comparable service. A coordinator monitors a state of each member of the composite resource. A component requests the service from the coordinator. The coordinator arranges for the service to be provided to the component by a particular member of the composite resource. When the particular member ceases to be active, the service is automatically provided to the component by another member in the composite resource. A state of the composite resource is maintained independently of the state of each member in the composite resource.

Claims

1. A method of managing a plurality of components from a framework, the method comprising the steps of:

establishing a composite resource that includes a plurality of members residing on a plurality of nodes in a networked system, where each member of said plurality of said members is capable of providing a common service, wherein said composite resource is configured to remain active as long as specified conditions are satisfied, wherein said specified conditions correspond to a user-specified minimum number of active members in the composite resource or to a user-specified minimum service level for the composite resource;

monitoring, using framework resources, a state of each member of said composite resource;

causing a component that requires said common service to request said common service from said framework resources;

providing said common service to said component by;

arranging, by said framework resources, for said common service to be provided to said component by a member of said composite resource, wherein any active member of the composite resource can be used to provide the common service to the component;

when said member arranged to provide the common service ceases to be active, automatically causing said common service to be provided to said component by another member of said plurality of members, wherein any active member can be used to provide the common service to the component;

maintaining a state of the composite resource independently of the state of each member of said composite resource such that the state of the composite resource remains active so long as said specified conditions are satisfied;

continuously providing the common service from a member of the composite resource after the composite resource ceases to be active;

in response to detecting that said specified conditions are satisfied, said composite resource ceasing to be active; and

while not active, the composite resource continuing to be executed but no longer servicing requests for said common service.

2. The method of claim 1, wherein the plurality of members includes a set of active members and a set of inactive members, wherein members in the set of active members provide the common service in a manner that is different than the manner used by members in the set of inactive members.

3. The method of claim 1, further comprising the step of evaluating the state of the composite resource in response to one or more of the members in the plurality of members ceasing to be active.

4. The method of claim 1, further comprising the step of configuring the composite resource through framework resources based on a user-defined criteria.

5. The method of claim 1, further comprising the step of stopping the composite resource through the framework resources, so that each member in the plurality of members is stopped.

6. The method of claim 2, further comprising relocating a source of the composite resource from a node where a member in the inactive set of members resides to a node where a member in the active set of members resides, wherein just prior to performing the step of relocating the source of the composite resource, at least one of the active plurality of members was a member of the inactive set of members before the source of the composite resource was relocated.

7. The method of claim 1, further comprising measuring a performance characteristic of the composite resource from the framework resources.

8. The method of claim 1, further comprising providing an interface to enable an administrator to perform one or more operations on the composite resource through the framework resources.

9. The method of claim 1, further comprising enabling the component to be dependent on the common service irrespective of which of the plurality of members is providing the common service.

10. The method of claim 1, wherein establishing a composite resource includes enabling each of the plurality of members of the composite resource to be used with a set of resources on each member'"'"'s node, wherein the set of resources on each member'"'"'s node is required by the member to provide the service.

11. The method of claim 1, wherein the step of providing said service to said component includes:

arranging for said service to be provided to said component by a first member of said composite resource from a node on which the first member resides;

when the first member fails, causing the service to be provided to said component by a second member in the plurality of members from a node on which the second member resides, wherein the node on which the second member resides is different than the node on which the first member resides; and

wherein prior to the first member failing, the method further includes the step of enabling the second member to provide the service to the component using a set of resources on the node on which the second member resides, the set of resources on the node on which the second member resides being required by the second member to provide the service.

12. The method of claim 1, wherein providing said service to said component includes performing at least one of reading data from and writing data to a data source that is shared by the plurality of members.

13. The method of claim 11, further comprising detecting that the first member has failed, but that the node on which the first member resides is still operative, and wherein the step of causing the service to be provided to said component by a second member is performed while one or more other resources on the node on which the first member resides are operative.

14. The method of claim 13, further comprising the step of automatically restarting the first member after detecting that the first member has failed.

15. The method of claim 13, wherein the step of causing the service to be provided to said component by a second member is performed while attempting recovery of the first member.

16. The method of claim 1, wherein establishing a composite resource includes enabling a plurality of instances of a database application to be executed on the plurality of nodes.

17. The method of claim 1, wherein the composite resource is viewed by the framework as at least partially residing on a particular node in the plurality of nodes.

18. The method of claim 1, wherein said framework is distributed onto the plurality of nodes.

19. The method of claim 1, further comprising the step of executing an application on a first node in the plurality of nodes, wherein the application depends on the composite resource.

20. The method of claim 19, further comprising providing the common service to the application executing on the first node from a first member in the plurality of members, wherein the first member resides on the first node, and wherein in response to the first member ceasing to provide the common service, the method further comprises terminating execution of the application.

21. The method of claim 19, further comprising providing the common service to the application executing on the first node from a first member in the plurality of members, wherein the first member resides on the first node, and wherein in response to the first member ceasing to provide the service, the method further comprises providing the common service to the application executing on the first node from a second member in the plurality of members that resides on a second node in the plurality of nodes.

22. The method of claim 1, wherein the method further comprises:

initiating a member as part of the composite resource while the composite resource is running; and

in response to the member being initiated as a member of the composite resource, causing said initiated member to ensure that the composite resource is running.

23. A computer readable non-volatile or volatile medium storing one or more sequences of instructions for managing a plurality of components from a framework, wherein execution of the one or more sequences of instructions by one or more processors causes the one or more processors to perform the steps of:

establishing a composite resource that includes a plurality of members residing on a plurality of nodes in a networked system, where each member of said plurality of said members is capable of providing a common service, wherein said composite resource is configured to remain active as long as specified conditions are satisfied, wherein said specified conditions correspond to a user-specified minimum number of active members in the composite resource or to a user-specified minimum service level for the composite resource;

monitoring, using framework resources, a state of each member of said composite resource;

causing a component that requires said common service to request said common service from said framework resources;

providing said common service to said component by;

arranging, by said framework resources, for said common service to be provided to said component by a member of said composite resource, wherein any active member of the composite resource can be used to provide the common service to the component;

when said member arranged to provide the common service ceases to be active, automatically causing said common service to be provided to said component by another member of said plurality of members, wherein any active member can be used to provide the common service to the component;

maintaining a state of the composite resource independently of the state of each member of said composite resource such that the state of the composite resource remains active so long as said specified conditions are satisfied;

continuously providing the common service from a member of the composite resource after the composite resource ceases to be active;

in response to detecting that said specified conditions are satisfied, said composite resource ceasing to be active; and

while not active, the composite resource continuing to be executed but no longer servicing requests for said common service.

24. The computer readable medium of claim 23, wherein the plurality of members includes a set of active members and a set of inactive members, and wherein members in the set of active members provide the common service in a manner that is different than the manner used by members in the set of inactive members.

25. The computer readable medium of claim 23, further comprising instructions for evaluating the state of the composite resource in response to one or more members in said plurality of members ceasing to be active.

26. The computer readable medium of claim 23, further comprising instructions for configuring the composite resource through the framework resources based on a user-defined criteria.

27. The computer readable medium of claim 23, further comprising instructions for stopping the composite resource through the framework resources, so that each member in the plurality of members is stopped.

28. The computer readable medium of claim 24, further comprising instructions for relocating a source of the composite resource from a node where a member in the inactive set of members resides to a node where a member in the active set of members resides, wherein just prior to performing the step of relocating the source of the composite resource, at least one of the active plurality of members was a member of the inactive set of members before the source of the composite resource was relocated.

29. The computer readable medium of claim 23, further comprising instructions for measuring a performance characteristic of the composite resource from the framework resources.

30. The computer readable medium of claim 23, further comprising instructions for providing an interface to enable an administrator to perform one or more operations on the composite resource through the framework resources.

31. The computer readable medium of claim 23, further comprising instructions for enabling the component to be dependent on the common service irrespective of which of the plurality of members is providing the common service.

32. The computer readable medium of claim 23, wherein the instructions for establishing a composite resource include instructions for enabling each of the plurality of members of the composite resource to be used with a set of resources on each member'"'"'s node, wherein the set of resources on each member'"'"'s node is required by the member to provide the service.

33. The computer readable medium of claim 23, wherein instructions for providing said service to said component include instructions for performing the steps of:

arranging for said service to be provided to said component by a first member of said composite resource from a node on which the first member resides;

when the first member ceases to be active, causing the service to be provided to said component by a second member in the plurality of members from a node on which the second member resides, wherein the node on which the second member resides is different than the node on which the first member resides; and

wherein prior to the first member ceasing to be active, the computer-readable medium further includes instructions for performing the step of enabling the second member to provide the service to the component using a set of resources on the node on which the second member resides, the set of resources on the node on which the second member resides being required by the second member to provide the service.

34. The computer readable medium of claim 23, wherein instructions for providing said service to said component include instructions for performing at least one of reading data from and writing data to a data source that is shared by the plurality of members.

35. The computer readable medium of claim 33, further comprising instructions for detecting that the first member has failed, but that the node on which the first member resides is still operative, and wherein the step of causing the service to be provided to said component by a second member is performed while one or more other resources on the node on which the first member resides are operative.

36. The computer readable medium of claim 35, wherein instructions for performing the step of causing the service to be provided to said component by a second member include instructions so that said step is performed while attempting recovery of the first member.

37. The computer readable medium of claim 23, wherein instructions for establishing a composite resource include instructions for enabling a plurality of instances of a database application to be executed on the plurality of nodes.

38. The computer readable medium of claim 23 wherein the composite resource is viewed by the framework as at least partially residing on a particular node in said plurality of nodes.

39. The computer readable medium of claim 23, wherein said framework is distributed onto the plurality of nodes.

40. The computer readable medium of claim 23, further comprising instructions for performing the step of executing an application on a first node in the plurality of nodes, wherein the application depends on the composite resource.

41. The computer readable medium of claim 40, further comprising instructions for providing the common service to the application executing on the first node from a first member in the plurality of members, wherein the first member resides on the first node, and wherein in response to the first member ceasing to provide the common service, the computer readable medium further comprises instructions for terminating execution of the application.

42. The computer readable medium of claim 40, further comprising instructions for providing the common service to the application executing on the first node from a first member in the plurality of members, wherein the first member resides on the first node, and wherein in response to the first member ceasing to provide the service, the computer readable medium further comprises instructions for providing the common service to the application executing on the first node from a second member in the plurality of members that resides on a second node in the plurality of nodes.

43. The computer readable medium of claim 23, wherein the computer readable medium further comprises instructions for performing the steps of:

initiating a member as part of the composite resource while the composite resource is running; and

in response to the member being initiated as a member of the composite resource, causing said initiated member to ensure that the composite resource is running.

44. A computer readable non-volatile or volatile medium storing one or more sequences of instructions for managing a plurality of components from a framework, wherein execution of the one or more sequences of instructions by one or more processors causes the one or more processors to perform the steps of:

establishing a composite resource that includes a first plurality of members and a second plurality of members, the first and second pluralities of members residing on a plurality of nodes in a networked system, each of said first plurality of members being able to provide a common service, and each of said second plurality of members being able to provide the common service when activated;

wherein a state of the composite resource is maintained independently of a state of each member that is active in the composite resource, such that the state of the composite resource remains active so long as specified conditions are satisfied, wherein said specified conditions correspond to a user-specified minimum number of active members in the composite resource or to a user-specified minimum service level for the composite resource;

arranging, by said framework, for a member in the first plurality of members to provide the service to a first component that requests the common service, wherein any member of the first plurality of members can be used to provide the service to the first component;

in response to one or more of the members in the first plurality of members becoming inactive,

further comprising instructions for performing the steps of;

activating a member in the second plurality of members; and

automatically providing the common service using an active member in one of the first plurality of members or the second plurality of members.

45. The computer readable medium of claim 44, wherein instructions for automatically providing the common service using an active member in one of the first plurality of members or the second plurality of members include instructions for maintaining a cardinality of the members that are active to provide the common service of the composite resource.

46. The computer readable medium of claim 45, further comprising instructions for performing the step of expanding the cardinality by activating multiple members in the second plurality of members into providing the common service.

47. The computer readable medium of claim 44, wherein instructions for arranging for a member in the first plurality of members to provide the common service include instructions for using resources of the framework shared by the first plurality of members and the second plurality of members.

48. The computer readable medium of claim 47, further comprising instructions for maintaining status information about the first plurality of members and the second plurality of members through the framework resources.