System and method for a scalable notification server providing

• US 20040143659A1
• Filed: 10/23/2003
• Published: 07/22/2004
• Est. Priority Date: 04/26/2002
• Status: Abandoned Application

• Current Assignee: Arthur W. Westerberg, Eswaran Subrahmanian, Russell C. Milliken
• Original Assignee: Arthur W. Westerberg, Eswaran Subrahmanian, Russell C. Milliken
• Inventors: Westerberg, Arthur W, Subrahmanian, Eswaran, Milliken, Russell C.
• Application Number:
  US10/475,795
• Publication Number:
  US 20040143659A1
• Time in Patent Office: Days
• US Class Current: 709/224
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers
• CPC Class Codes: H04L 67/10015 Access to distributed or replicated servers, e.g. using brokers
• CPC Class Codes: H04L 67/1095 Replication or mirroring of data, e.g. scheduling or transport for data synchronisation between network nodes
• CPC Class Codes: H04L 67/535 Tracking the activity of the user network monitoring arrangements H04L43/00; recording of computer activity G06F11/34
• CPC Class Codes: H04L 69/329 in the application layer [OSI layer 7]
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

A method of servicing complex interests for a plurality of client applications or subscribers (8-10), includes specifying a plurality of complex interests from the applications or subscribers (8-10). At least one of the complex interests is formed from a plurality of constituent simple interests. A plurality of constraints are specified over the constituent simple interests. A plurality of event filters are specified from the applications or subscribers (8-10). A plurality of simple event filters (5), which match the constituent simple interests, are employed as at least one of the event filters. A set of events, which matches the at least one of the complex interests, is detected. One application or subscriber (8-10) is notified when the set of events is detected. At least one server (7) is employed to detect the set of events and notify the one application or subscriber (8-1) when the set of events is detected. The at least one server (7) is scaled.

Claims

1. A method of servicing complex interests for a plurality of client applications or subscribers, said method comprising:

specifying a plurality of complex interests from the client applications or the subscribers;

forming at least one of the complex interests from a plurality of constituent simple interests;

specifying a plurality of constraints over said constituent simple interests;

specifying a plurality of event filters from the client applications or the subscribers;

employing as at least one of the event filters a plurality of simple event filters, which match the constituent simple interests;

detecting a set of events, which set matches said at least one of the complex interests;

notifying one of the client applications or the subscribers when said set of events is detected;

employing at least one server to detect said set of events and to notify said one of said client applications or the subscribers when said set of events is detected; and

scaling said at least one server.

2. The method of claim 1 further comprising

mimicking a simple notification service to notify one of the client applications of an event passing through one of the event filters.

3. The method of claim 1 further comprising

employing application wrappers to communicate with said client applications.

4. The method of claim 1 further comprising

employing a plurality of servers as said at least one server.

5. The method of claim 4 further comprising

employing a plurality of complex interest servers and at least one simple interest server as said at least one server.

6. The method of claim 5 further comprising

adding or removing said complex interest servers as a function of performance of said complex interest servers and said at least one simple interest server.

7. A scalable simple and complex interests notification system for a plurality of client applications or subscribers, said system comprising:

means for specifying a plurality of complex interests from the client applications or the subscribers and forming at least one of the complex interests from a plurality of constituent simple interests, with a plurality of constraints specified over the constituent simple interests;

means for receiving a plurality of event filters from the client applications or the subscribers;

means for matching the constituent simple interests from a plurality of simple event filters;

at least one server detecting a set of events, which set matches said at least one of the complex interests, and notifying one of said client applications or the subscribers when said set of events is detected; and

means for scaling said at least one server.

8. The system of claim 7 wherein said at least one server is a plurality of complex interest servers and at least one simple interest server.

9. The system of claim 7 wherein said at least one server mimics a simple notification service to notify one of the client applications of said set of events, which set matches one of the complex interests.

10. A method for providing a feedback measure for a server, said method comprising:

reporting an event from a client to said server,

determining a first time at said client associated with said reporting said event;

receiving a callback at said client or an interested party from said server responsive to said reporting said event;

determining a second time at said client or at said interested party associated with said receiving said callback; and

employing a difference between said first and second times as said feedback measure.

11. The method of claim 10 further comprising

employing a notification server as said server;

and

providing said feedback measure to said notification server.

12. The method of claim 11 further comprising

employing said feedback measure to evaluate time taken to service an interest by said notification server.

13. The method of claim 11 further comprising

employing said feedback measure to evaluate when to scale said notification server.

14. The method of claim 11 further comprising

employing a complex interest server as said notification server.

15. The method of claim 11 further comprising

employing a simple interest server as said notification server.

16. The method of claim 15 further comprising

employing an OMG Notification Server as said simple interest server.

17. The method of claim 10 further comprising

employing said feedback measure to evaluate when to scale said server.

18. The method of claim 17 further comprising

employing a scaling function in said server;

inputting said feedback measure by said scaling function; and

spawning another instance of said server if said feedback measure is greater than a threshold value.

19. The method of claim 18 further comprising

employing a value greater than zero as said threshold value.

20. The method of claim 18 further comprising

employing zero as said threshold value.

21. The method of claim 10 further comprising

receiving said callback at said client from said server responsive to said reporting said event;

determining said second time at said client associated with said receiving said callback; and

determining said difference between said first and second times at said client.

22. The method of claim 10 further comprising

receiving said callback at said interest party from said server responsive to said reporting said event;

determining said second time at said interested party associated with said receiving said callback;

employing a first clock at said client to determine said first time;

employing a second clock at said interested party to determine said second time; and

synchronizing said first and second clocks.

23. The method of claim 10 further comprising

employing said feedback measure to monitor performance of said server.

24. A measuring notification client apparatus for providing a feedback measure for a notification server, said measuring notification client apparatus comprising:

means for reporting an event at a first time to said server;

means for determining the first time associated with said event;

means for receiving a callback at a second time from said server responsive to said event;

means for determining the second time associated with said callback; and

means for determining a difference between said first and second times as said feedback measure.

25. The measuring notification client apparatus of claim 24 wherein said means for determining a difference includes means for reporting said feedback measure to said server.

26. A method for scaling a notification server, said method comprising:

employing a first notification server as said notification server;

servicing a plurality of client applications and a plurality of interests at said first notification server;

receiving a feedback measure associated with said first notification server;

determining if said feedback measure is greater than a threshold value and responsively spawning a second notification server; and

transferring some of said client applications and some of said interests from the first notification server to the second notification server.

27. The method of claim 26 further comprising

employing a first complex interest server as said first notification server;

and

employing a second complex interest server as said second notification server.

28. The method of claim 27 further comprising

spawning the second complex interest server from the first complex interest server.

29. The method of claim 26 further comprising

employing a first simple interest server as said first notification server;

and

employing a second simple interest server as said second notification server.

30. The method of claim 29 further comprising

spawning the second simple interest server from the first simple interest server.

31. The method of claim 26 further comprising

measuring performance of said first notification server;

and

transferring said some of said client applications and said some of said interests from the first notification server to the second notification server until said first notification server has transferred a predetermined proportion of said client applications and said interests based on said performance.

32. The method of claim 26 further comprising

spawning said second notification server from a third notification server.

33. The method of claim 26 further comprising

employing a first simple and complex interest server as said first notification server;

and

employing a second simple and complex interest server as said second notification server.

34. The method of claim 33 further comprising

employing at least one complex interest formed from a plurality of constituent simple interests for each of the client applications;

counting the simple constituent interests for each of the client applications at said first notification server; and

ordering said client applications based upon descending count of said simple constituent interests for each of the client applications.

35. The method of claim 34 further comprising

counting partially matched complex interests for each of the client applications at said first-notification server;

and

ordering said client applications based upon descending count of said partially matched complex interests for each of the client applications having identical counts of said simple constituent interests.

36. The method of claim 35 further comprising

employing a simple interest server and a complex interest server as said first notification server;

determining if said complex interest server is processor bound or memory bound; and

for each of the client applications having identical counts of said simple constituent interests and identical counts of said partially matched complex interests, ordering said client applications based upon said client applications having most recently matched an incoming notification from said simple interest server if said complex interest server is processor bound and, alternatively, ordering said client applications based upon said client applications having least recently matched an incoming notification from said simple interest server if said complex interest server is memory bound.

37. The method of claim 36 further comprising

employing a first simple interest server and a first complex interest server as said first notification server;

counting a total number of the constituent simple interests registered with the first complex interest server;

employing a second simple interest server and a second complex interest server as said second notification server; and

spawning the second complex interest server.

38. The method of claim 37 further comprising

employing a first computer as said first complex interest server and a second different computer as said second complex interest server.

39. The method of claim 37 further comprising

ordering said client applications in a list;

initializing a count of constituent moved simple interests to zero; and

choosing one of said client applications from said list to move from said first complex interest server to said second complex interest server until said list is empty or until said count of constituent moved simple interests is greater than a predetermined proportion of said total number of the constituent simple interests registered with the first complex interest server.

40. The method of claim 26 further comprising

spawning said second notification server and a third notification server from said first notification server;

transferring a first set of said client applications and said interests from the first notification server to the second notification server;

transferring a second different set of said client applications and said interests from the first notification server to the third notification server; and

terminating said first notification server.

41. The method of claim 31 comprising

employing about one half as said predetermined proportion.

42. The method of claim 39 comprising

employing about one half as said predetermined proportion.