Efficient maintenance of a distributed system membership view

• US 10,567,496 B2
• Filed: 08/24/2017
• Issued: 02/18/2020
• Est. Priority Date: 02/17/2009
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Garces-Erice, Luis
• Primary Examiner(s): Keehn, Richard G
• Application Number:
  US15/685,218
• Publication Number:
  US 20170353547A1
• Time in Patent Office: 908 Days
• CPC Class Codes: G06F 15/163 Interprocessor communication
• CPC Class Codes: G06F 15/173 using an interconnection network, e.g. matrix, shuffle, pyramid, star, snowflake
• CPC Class Codes: G06Q 30/02 Marketing; Price estimation or determination; Fundraising
• CPC Class Codes: H04L 67/1046 Joining mechanisms
• CPC Class Codes: H04L 67/1053 with pre-configuration of logical or physical connections with a determined number of other peers
• CPC Class Codes: H04L 67/51 Discovery or management thereof, e.g. service location protocol [SLP] or web services
• CPC Class Codes: H04W 4/08 User group management
• CPC Class Codes: H04W 8/186 Processing of subscriber group data

Abstract

A method, system and computer program product are disclosed for maintaining a membership view of a distributed computing system comprising a multitude of members, wherein each of said members sends out a message indicating that said each of the members is available in the system. In one embodiment, the method comprises maintaining a first list of at least some of the members in the distributed system; and over a period of time, when one of the members sends out the message indicating that said one of the members is available in the distributed system, adding said one of the members to a second list. At defined times, the first list is replaced with the second list. In an embodiment, the method further comprises at said defined times, starting a new, empty second list.

Claims

1. A method of using a listening list to determine updates to a working list of a membership view of members of a distributed computing system, wherein, the working list comprises a list of current members of the distributed computing system;

during a given period of time, each of one or more of said current member of the computing system generates a membership signal to indicate that said each current member is a member of the computing system; and

during the given period of time, new members join the distributed computing system, and each of the new members generates the membership signal to indicate that said each new member is active in the distributed computing system, the method comprising;

maintaining the working list of a membership view of members of the distributed computing system;

maintaining a listening list to list the members of the distributed computing system; and

during a defined period of time, monitoring for the membership signals; and

whenever one of the membership signals is detected,

determining if the one of the members that generated the detected membership signal is on the listening list,

if said one of the members is on the listening list, keeping the working list unchanged, and

if said one of the members is not on the listening list, adding said one of the members to the listening list and to the working list.

2. The method according to claim 1, further comprising at a specified time, replacing the working list with the listening list to form a new working list.

3. The method according to claim 2, wherein the new working list identifies those members of the computing system that generated the membership signal during the given period of time.

4. The method according to claim 2, further comprising starting a new, empty listening list at the specified time.

5. The method according to claim 2, wherein the maintaining a listening list includes during the given period of time, adding to the listening list only the members of the computing system that generated the memberships signal during the given period of time.

6. The method according to claim 5, wherein the replacing the working list with the listening list to form a new working list includes replacing the working list with the listening list to form a new working list identifying only those members of the computing system that, during the given time period, generated the membership signal.

7. The method according to claim 2, wherein said specified time is at the end of the given period of time.

8. The method according to claim 1, wherein each of the members in the computing system generates the membership signal in a defined time period, and the given time period is longer than the defined time period.

9. The method according to claim 8, wherein the given time period is three times as long as the defined time period.

10. The method according to claim 1, wherein over said given period of time, the listening list becomes an updated, complete list of all the members in the distributed computing system that, during said given time period, generated the membership signal.

11. A membership updating system for using a listening list to determine updates to a working list of a membership view of members of a distributed computing system, wherein, the working list comprises a list of current members of the distributed computing system;

during a given period of time, each of one or more of said current member of the computing system generates a membership signal to indicate that said each current member is a member of the computing system; and

during the given period of time, new members join the distributed computing system, and each of the new members generates the membership signal to indicate that said each new member is active in the distributed computing system, the membership updating system comprising;

a computer system comprising a memory for storing data, and one or more hardware processor units connected to the memory for transmitting data to and receiving data from the memory, the one or more hardware processor units configured for;

maintaining the working list of a membership view of members of the distributed computing system;

maintaining a listening list to list the members of the distributed computing system; and

during a defined period of time, monitoring for the membership signals; and

whenever one of the membership signals is detected,

determining if the one of the members that generated the detected membership signal is on the listening list,

if said one of the members is on the listening list, keeping the working list unchanged, and

if said one of the members is not on the listening list, adding said one of the members to the listening list and to the working list.

12. The membership updating system according to claim 11, wherein the one or more hardware processor units are configured for replacing the working list with the listening list at a specified time to form a new working list.

13. The membership updating system according to claim 12, wherein the new working list identifies those members of the computing system that generated the membership signal during the given period of time.

14. The membership updating system according to claim 12, wherein the one or more hardware processor units are configured for starting a new, empty listening list at the specified time.

15. The membership updating system according to claim 12, wherein the maintaining a listening list includes during the given period of time, adding to the listening list only the members of the computing system that generated the memberships signal during the given period of time.

16. An article of manufacture comprising:

at least one computer usable device having computer readable program code logic to execute a machine instruction in a processing member for keeping current a working list of a membership view of members of a distributed computing system, wherein, the working list comprises a list of current members of the distributed computing system;

during a given period of time, each of one or more of said current member of the computing system generates a membership signal to indicate that said each current member is a member of the computing system; and

during the given period of time, new members join the distributed computing system, and each of the new members generates the membership signal to indicate that said each new member is active in the distributed computing system, the computer readable program code logic, when executing, performing the following;

maintaining the working list of a membership view of members of the distributed computing system;

maintaining a listening list to list the members of the distributed computing system; and

during a defined period of time, monitoring for the membership signals; and

whenever one of the membership signals is detected,

determining if the one of the members that generated the detected membership signal is on the listening list,

if said one of the members is on the listening list, keeping the working list unchanged, and

if said one of the members is not on the listening list, adding said one of the members to the listening list and to the working list.

17. The article of manufacture according to claim 16, wherein the computer readable program code logic, when executing, performs the following:

at a specified time, replacing the working list with the listening list to form a new working list.

18. The article of manufacture according to claim 17, wherein the new working list identifies those members of the computing system that generated the membership signal during the given period of time.

19. The article of manufacture according to claim 17, wherein the computer readable program code logic, when executing, performs the following:

starting a new, empty listening list at the specified time.

20. The article of manufacture according to claim 17, wherein the maintaining a listening list includes during the given period of time, adding to the listening list only the members of the computing system that generated the memberships signal during the given period of time.