Combined join and state transfer

• US 20090219945A1
• Filed: 02/28/2008
• Published: 09/03/2009
• Est. Priority Date: 02/28/2008
• Status: Active Grant

• Current Assignee: Red Hat, Inc. (International Business Machines Corporation)
• Original Assignee: Red Hat, Inc. (International Business Machines Corporation)
• Inventors: Blagojevic, Vladimir, Ban, Bela
• Granted Patent: US 8,312,084 B2
• Time in Patent Office: Days
• US Class Current: 370/432
• CPC Class Codes: H04L 12/1822 Conducting the conference, e.g. admission, detection, selection or grouping of participants, correlating users to one or more conference sessions, prioritising transmission
• CPC Class Codes: H04L 12/185 with management of multicast group membership

Abstract

A method and apparatus for processing messages is described. In one embodiment, an application programming interface provides for a flush protocol to force members of a group to send all of their pending messages prior to a predetermined event. A client sends a request to a coordinator of the group to join the group and to transfer a state of the group to the client. The application programming interface performs a single flush operation on the group in response to the request.

Claims

1. A computer-implemented method comprising:

configuring a flush protocol to force members of a group to send all of their pending messages prior to a predetermined event;

receiving a request from a client to join the group and to transfer a state of the group to the client; and

performing a single flush protocol on the group in response to the request.

2. The computer-implemented method of claim 1 further comprising:

identifying members of the group and a coordinator associated with the group,

wherein the client requests the coordinator to perform the flush protocol upon joining the group.

3. The computer-implemented method of claim 2 wherein the request to transfer the state of the group includes a request to see a same set of messages in a same view prior to installing a new view.

4. The computer-implemented method of claim 2 further comprising:

intercepting the request to transfer the state of the group; and

replacing the request to transfer the state of the group with a request to join the state of the group without performing another flush protocol.

5. The computer-implemented method of claim 4 wherein the request to join the state of the group includes a flush flag parameter, the flush flag parameter including a boolean operator corresponding to an operation of the flush protocol.

6. The computer-implemented method of claim 5 further comprising:

generating a new view upon joining the client with the group;

sending the new view to the members of the group; and

receiving an acknowledgment from the members of the group of the new view.

7. The computer-implemented method of claim 6 wherein each members of the group includes a Java-based object.

8. An article of manufacture comprising:

a machine-accessible storage medium including data that, when accessed by a machine, cause the machine to perform a method comprising;

configuring a flush protocol to force members of a group to send all of their pending messages prior to a predetermined event;

receiving a request from a client to join the group and to transfer a state of the group to the client; and

performing a single flush protocol on the group in response to the request.

9. The article of manufacture of claim 8 wherein the method further comprises:

identifying members of the group and a coordinator associated with the group,

wherein the client requests the coordinator to perform the flush protocol upon joining the group.

10. The article of manufacture of claim 9 wherein the request to transfer the state of the group includes a request to see a same set of messages in a same view prior to installing a new view.

11. The article of manufacture of claim 9 wherein the method further comprises:

intercepting the request to transfer the state of the group; and

replacing the request to transfer the state of the group with a request to join the state of the group without performing another flush protocol.

12. The article of manufacture of claim 11 wherein the request to join the state of the group includes a flush flag parameter, the flush flag parameter including a boolean operator corresponding to an operation of the flush protocol.

13. The article of manufacture of claim 12 wherein the method further comprises:

generating a new view upon joining the client with the group;

sending the new view to the members of the group; and

receiving an acknowledgment from the members of the group of the new view.

14. The article of manufacture of claim 13 wherein each members of the group includes a Java-based object.

15. A system comprising:

a combining module to receive a request from a client to join and transfer a state of a group to the client;

a coordinator associated with the group, the coordinator coupled to the combining module to configure a flush protocol to force members of the group to send all of their pending messages prior to a predetermined event and to perform a single flush protocol on the group on behalf of the client in response to the request.

16. The system of claim 15 wherein the request to transfer the state of the group includes a request to see a same set of messages in a same view prior to installing a new view.

17. The system of claim 16 wherein the combining module includes:

an interceptor to intercept the client'"'"'s request to transfer the state of the group, and to replace the client'"'"'s request to transfer the state of the group with a request to join the state of the group without the coordinator having to perform another flush protocol.

18. The system of claim 17 wherein the request to join the state of the group includes a flush flag parameter, the flush flag parameter including a boolean operator corresponding to an operation of the flush protocol.

19. The system of claim 18 wherein the coordinator is to generate a new view upon joining the client with the group, to send the new view to the members of the group, and to receive an acknowledgment from the members of the group of the new view.

20. The system of claim 19 wherein each members of the group includes a Java-based object.