Dynamic reconfiguration of applications on a server

• US 20030101245A1
• Filed: 11/26/2001
• Published: 05/29/2003
• Est. Priority Date: 11/26/2001
• Status: Active Grant

• Current Assignee: Oracle America, Inc. (Oracle Corporation)
• Original Assignee: Sun Microsystems Incorporated (Oracle Corporation)
• Inventors: Srinivasan, Arvind, Chintalapati, Murthy
• Granted Patent: US 7,188,163 B2
• Time in Patent Office: Days
• US Class Current: 709/221
• CPC Class Codes: G06F 9/44505 Configuring for program initiating, e.g. using registry, configuration files
• CPC Class Codes: H04L 67/02 based on web technology, e.g. hypertext transfer protocol [HTTP]
• CPC Class Codes: H04L 67/14 Session management for real-time applications in data packet communications networks H04L65/1066
• CPC Class Codes: H04L 67/142 Managing session states for stateless protocols; Signalling session states; State transitions; Keeping-state mechanisms
• CPC Class Codes: H04L 67/34 involving the movement of software or configuration parameters network booting or remote initial program loading [RIPL] G06F9/4416
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

Methods for reconfiguring an application running on a server, without restarting the server, are described. Method steps include reading application configuration information related to a new version of the application, constructing an application configuration based on the application configuration information, and providing the application configuration to the server. Advantageously, an application runtime environment within the server services new application service requests related to the application by referencing the new application configuration, while old application configurations are maintained for servicing, without interruption, existing service requests related to the application.

Claims

1. In a computer system on which one or more applications execute, wherein a first application configuration is defined by first application configuration information, the first application configuration providing for execution of the application, a computer-implemented method for reconfiguring the application without restarting the computer system, comprising:

reading second application configuration information defining a reconfigured version of the application;

constructing a second application configuration based on the second application configuration information; and

providing the second application configuration to an application runtime environment for servicing new requests related to the application while maintaining the first application configuration for servicing existing requests related to the application.

2. The method of claim 1, further comprising:

destroying the first application configuration upon completion of all application service requests using the first application configuration, whereby computer system resources used to maintain the first application configuration are made available for other uses.

3. The method of claim 1, further comprising:

accessing persistent session information related to an existing application user session to use for servicing new requests from the same user during the existing application user session.

4. The method of claim 1, further comprising:

determining that the second application configuration successfully initialized prior to providing the second application configuration to the runtime environment for servicing new requests.

5. The method of claim 4, wherein the step of determining that the second application configuration successfully initialized is based on a communication from the application runtime environment.

6. The method of claim 1, further comprising:

receiving a request to reconfigure the computer system; and

reconfiguring the computer system in response to the request.

7. The method of claim 1, wherein constructing the second application configuration is further based on an application runtime environment configuration.

8. The method of claim 7 wherein constructing the second application configuration includes:

reading a timestamp associated with the second application configuration information; and

determining that the second application configuration information is different than the first application configuration information based on the timestamp.

9. The method of claim 1 wherein constructing the second application configuration includes:

reading a timestamp associated with a class file referenced in the second application configuration information;

determining that the class file has changed based on the timestamp; and

constructing the second application configuration, at least in part, according to the changed class file.

10. The method of claim 1, further comprising:

logging one or more messages related to providing the second application configuration to the computer system.

11. The method of claim 1, wherein providing the second application configuration comprises:

updating a current configuration reference to reference the second application configuration rather than the first application configuration.

12. The method of claim 11, wherein updating the current configuration reference is performed atomically.

13. The method of claim 1 wherein the first application configuration is maintained for servicing, without interruption, existing requests related to the application from an existing connection.

14. In a computer system on which one or more applications execute, wherein a former application configuration is defined by a first application configuration information and a current application configuration is defined by a second application configuration information, the application configurations providing for execution of the application, a computer-implemented method for processing application service requests, comprising:

completing processing a pending first request for an application service that is associated with the former application configuration;

receiving a second request for an application service;

associating the second request with the current application configuration;

accessing the second application configuration information defining the current application configuration; and

processing the second request according to the second application configuration information.

15. The method of claim 14 wherein the pending first request and the second request originate from the same user session, and wherein completing processing the pending first request and processing the second request are performed without restarting the computer system.

16. The method of claim 14, further comprising:

determining whether the first application configuration information is referenced by at least one pending process; and

deleting the first application configuration information from the computer system in response to determining that the first application configuration information is not referenced by at least one pending process.

17. The method of claim 16, wherein the first application configuration information occupies one or more blocks of memory, and wherein deleting the first application configuration comprises:

releasing the one or more blocks of memory.

18. The method of claim 16, wherein determining whether the first application configuration information is referenced by at least one pending process comprises:

determining whether a reference count is equal to a predetermined value indicating that no processes are referencing the first application configuration information.

19. In a computer system on which one or more applications execute, wherein a plurality of application configurations are defined by a plurality of associated application configuration information and one application configuration of the plurality of application configurations is the current configuration associated with a current version of a first application and two or more other application configurations of the plurality of application configurations are former configurations associated with former versions of the first application, a computer-implemented method for processing application service requests, comprising:

completing processing one or more pending requests for application services that are associated with any of the former configurations according to former configuration information that is associated with each of the one or more pending requests;

upon receiving a new request for an application service, accessing current application configuration information defining the current configuration; and

processing the new request according to the current application configuration information.

20. In a computer system on which one or more applications execute, wherein a current application configuration is defined by a first application configuration information, the current configuration providing for execution of the application, a computer-readable medium comprising instructions which, when executed by one or more processors, cause the one or more processors to reconfigure the application without restarting the computer system, by performing the steps of:

reading second application configuration information defining a reconfigured version of the application;

constructing a second application configuration based on the second application configuration information; and

providing the second application configuration to an application runtime environment for servicing new requests related to the application from a new connection while maintaining the first application configuration for servicing existing requests related to the application from an existing connection.

21. The computer readable medium of claim 20, wherein execution of the instructions by the one or more processors causes the one or more processors to perform:

destroying the first application configuration upon completion of all application service requests using the first application configuration, whereby computer system resources used to maintain the first application configuration are made available for other uses.

22. The computer readable medium of claim 20, wherein execution of the instructions by the one or more processors causes the one or more processors to perform:

accessing persistent session information related to an existing application user session to use for servicing new requests from the same user during the existing application user session.

23. The computer readable medium of claim 20, wherein execution of the instructions by the one or more processors causes the one or more processors to perform:

determining that the second application configuration successfully initialized prior to providing the second application configuration to the runtime environment for servicing new requests related to the application.

24. The computer readable medium of claim 23, wherein execution of the instructions by the one or more processors causes the one or more processors to perform the step of determining that the second application configuration successfully initialized based on a communication from the application runtime environment.

25. The computer readable medium of claim 20, wherein execution of the instructions by the one or more processors causes the one or more processors to perform:

receiving a request for reconfiguring the computer system absent any changes to the computer system configuration; and

reconfiguring the computer system based on the second application configuration in response to the request.

26. The computer-readable medium of claim 20, wherein constructing a second application configuration is based on the second application configuration information and an application runtime environment configuration, and wherein execution of the instructions by the one or more processors causes the one or more processors to perform providing the second application configuration to the server for servicing new requests related to the application according to the second application configuration.

27. The computer-readable medium of claim 26 wherein execution of the instructions by the one or more processors causes the one or more processors to perform constructing the second application configuration by performing the steps of:

reading a timestamp associated with the second application configuration information; and

determining that the second application configuration information is different than the first application configuration information based on the timestamp.

28. The computer-readable medium of claim 20 wherein execution of the instructions by the one or more processors causes the one or more processors to perform constructing the second application configuration by performing the steps of:

reading a timestamp associated with a class file referenced in the second application configuration information;

determining that the class file has changed based on the timestamp; and

constructing the second application configuration, at least in part, according to the changed class file.

29. The computer readable medium of claim 20, wherein execution of the instructions by the one or more processors causes the one or more processors to perform:

logging one or more messages related to providing the second application configuration to the computer system.

30. The computer-readable medium of claim 20 wherein execution of the instructions by the one or more processors causes the one or more processors to perform providing the second application configuration by performing the steps of:

updating a current configuration reference to reference the second application configuration rather than the first application configuration.

31. The computer-readable medium of claim 30 wherein execution of the instructions by the one or more processors causes the one or more processors to perform updating the current configuration reference atomically.

32. In a computer system on which one or more applications execute, wherein a former application configuration is defined by a first application configuration information and a current application configuration is defined by a second application configuration information, the application configurations providing for execution of the application, a computer-readable medium comprising instructions which, when executed by one or more processors, cause the one or more processors to process application service requests, by performing the steps of:

completing processing a pending first request for an application service that is associated with the former application configuration;

receiving a second request for an application service;

associating the second request with the current application configuration;

accessing the second application configuration information defining the current application configuration; and

processing the second request according to the second application configuration information.

33. The computer-readable medium of claim 32 wherein the pending first request and the second request originate from the same user session, and wherein execution of the instructions by the one or more processors causes the one or more processors to perform completing processing the pending first request and processing the second request without having to restart the computer system.

34. The computer-readable medium of claim 32 wherein execution of the instructions by the one or more processors causes the one or more processors to perform the steps of:

determining whether the first application configuration information is referenced by at least one pending process; and

deleting the first application configuration information from the computer system in response to determining that the first application configuration information is not referenced by at least one pending process.

35. The computer-readable medium of claim 34, wherein the first application configuration information occupies one or more blocks of memory, and wherein execution of the instructions by the one or more processors causes the one or more processors to perform deleting the first application configuration by performing:

releasing the one or more blocks of memory.

36. The computer-readable medium of claim 34, wherein execution of the instructions by the one or more processors causes the one or more processors to perform determining whether the first application configuration information is referenced by at least one pending process by performing:

determining whether a reference count associated with the first application configuration information is equal to a predetermined value indicating that no processes are referencing the first application configuration information.

37. The computer readable medium of claim 36, wherein execution of the instructions by the one or more processors causes the one or more processors to perform determining that the second application configuration successfully initialized based on a communication from an application runtime environment.

38. An apparatus on which one or more applications execute, wherein a first application configuration is defined by first application configuration information, the first application configuration providing for execution of the application, the apparatus comprising:

a network interface;

a memory; and

one or more processors connected to the network interface and the memory, the one or more processors configured for

reading second application configuration information defining a reconfigured version of the application;

constructing a second application configuration based on the second application configuration information; and

providing the second application configuration to an application runtime environment for servicing new requests related to the application while maintaining the first application configuration for servicing existing requests related to the application.