Fast reorganization of connections in response to an event in a clustered computing system

• US 20050038801A1
• Filed: 08/12/2004
• Published: 02/17/2005
• Est. Priority Date: 08/14/2003
• Status: Active Grant

• Current Assignee: Oracle International Corporation (Oracle Corporation)
• Original Assignee: Oracle International Corporation (Oracle Corporation)
• Inventors: Irudayaraj, Rajkumar, Colrain, Carol
• Granted Patent: US 7,953,860 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 11/1443 Transmit or communication errors
• CPC Class Codes: G06F 16/21 Design, administration or maintenance of databases

Abstract

Techniques for fast recovery and/or balancing of connections to a clustered computing system provide management of such connections by determining a number of connections to load balance across nodes and by triggering creation of such connections. In one aspect, a notification of an event regarding the clustered computing system is received by a connection pool manager, a pool of connections to the system is identified based on the notification, and one or more connections from the pool are processed in response to the event. According to an embodiment, the notification comprises the identities of the service, database, server instance and machine that correspond to the event.

Claims

1. A method comprising the computer-implemented steps of:

receiving a notification of an event regarding a clustered computing system;

based on said notification, identifying a pool of connections to said system; and

in response to said event, processing one or more connections from said pool, wherein said processing changes availability of said one or more connections for use by one or more clients for connecting to said system.

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

recording the location of sessions associated with connections from said pool of connections; and

identifying said one or more connections for said processing based on said location of sessions matching information in said notification.

3. The method of claim 1, the method further comprising the computer-implemented step of:

wherein the step of identifying includes identifying a pool that is associated with one or more service that is identified in said notification; and

wherein said processing includes invoking a process to create one or more connections in association with said pool of connections.

4. The method of claim 3, wherein invoking a process to create one or more connections includes invoking a process on a clustered database server, and wherein said process allocates said one or more connections across said clustered database server based on state changes that are associated with said particular service that is hosted by one or more instances associated with said clustered database server.

5. The method of claim 3, wherein said particular service is hosted by one or more instances associated with a clustered database server.

6. The method of claim 3, wherein said particular service is hosted by one or more instances associated with a clustered database server configured in a plurality of clusters that are processing instructions as a computing grid.

7. The method of claim 1,

wherein said notification identifies termination of a particular service that was hosted on a particular server instance of said system;

wherein said identifying includes identifying a pool that is associated with (a) said particular service, (b) a database being used in said system, (c) said particular server instance, and (d) a node of said system, that are identified in said notification; and

wherein said processing of connections includes

identifying one or more connections, from said pool, that is associated with said database and said particular server instance,

marking said one or more connections as invalid, and

aborting said one or more connections so one or more clients are interrupted.

8. The method of claim 1,

wherein said notification identifies start of a particular service that is hosted on a particular server instance of said system;

wherein said processing of connections includes

identifying a first number of said one or more connections that are removed from said pool; and

determining, based on said first number, a second number of said one or more connections for allocating across a plurality of active server instances that host said particular service.

9. The method of claim 8, further comprising the computer-implemented step of:

requesting creation of at least a portion of said second number of said one or more connections, for immediate allocation across said plurality of active server instances that host said particular service.

10. The method of claim 9, wherein determining said second number includes determining said second number by dividing said first number by a number of said plurality of active server instances that host said particular service.

11. The method of claim 10, wherein

if said second number is not greater than zero, then

closing a subset of connections from said pool,

recreating said subset of connections in association with said pool for allocating said subset of connections to said plurality of active server instances that host said particular service.

12. The method of claim 11, wherein allocating said subset of connections is based on server performance metrics that are associated with said plurality of active server instances that host said particular service.

13. The method of claim 1,

wherein said notification identifies termination of a node that is hosting one or more server instance that is hosting at least a portion of a particular service that is provided by said system;

wherein said identifying includes identifying a pool that is associated with said particular service that is identified in said notification; and

wherein said processing of connections includes

identifying one or more connections from said pool that are associated with said node;

marking said one or more connections as invalid, and

aborting said one or more connections so that one or more clients are interrupted.

14. The method of claim 13, wherein said aborting includes interrupting TCP/IP-based communications associated with said one or more connections.

15. The method of claim 13, wherein said aborting allows said one or more clients to quickly recover from said event.

16. A computer-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 1.

17. A computer-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 2.

18. A computer-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 3.

19. A computer-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 4.

20. A computer-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 5.

21. A computer-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 6.

22. A computer-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 7.

23. A computer-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 8.

24. A computer-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 9.

25. A computer-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 10.

26. A computer-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 11.

27. A computer-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 12.

28. A computer-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 13.

29. A computer-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 14.

30. A connection management system comprising:

one or more set of connections to a clustered computing system, wherein each set of connections is associated with a service that is provided by said clustered computing system; and

a connection pool manager that changes availability of one or more connection from a set of said one or more set of connections for use by one or more clients for connecting to said clustered computing system, based on information that is associated with an event occurring in said clustered computing system and automatically in response to receiving said information.

31. The system of claim 30 further comprising:

a notification system that generates event information based on events occurring in said clustered computing system;

a notification service mechanism that receives said event information and that notifies an event handler regarding said event; and

said event handler that transmits at least a portion of said event information to said connection pool manager.

32. The system of claim 30 wherein said clustered computing system comprises a listener process that receives a command from said connection pool manager to create said one or more connection, and wherein said listener process selects an instance and returns the address of said instance to the connection pool manager, which creates said one or more connection.