System and method for supporting mixed-phase transactions in an object-oriented environment

• US 6,061,708 A
• Filed: 05/31/1997
• Issued: 05/09/2000
• Est. Priority Date: 05/31/1997
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Kan, Teresa Chung, McKeehan, Michael Dennis
• Primary Examiner(s): Oberley, Alvin E.
• Assistant Examiner(s): BULLOCK JR, LEWIS ALEXANDER
• Application Number:
  US08/866,948
• Time in Patent Office: 1,074 Days
• Field of Search: 395/671, 395/683, 395/680, 709/101, 707/201, 707/202, 707/103
• US Class Current: 718/101
• CPC Class Codes: G06F 9/466 Transaction processing

Abstract

A system, method, and apparatus for ensuring data integrity in a distributed object-oriented transaction processing environment, including support of single- and two-phased commit protocol transactions with a new protocol defined as a mixed-phase commit protocol. A root transaction manager on a server registers distributed object resources requested by a client application for a global transaction as being committable by either the single-phase, two-phase, or mixed-phase protocol. The root transaction manager commits the registered resources in accordance with the results of the registration step.

Claims

1. A method for supporting a plurality of different commit procedures in a distributed object-oriented transaction processing environment, the method comprising the steps, all performed within a single global transaction commit cycle, of:

a transaction manager on a first server selectively registering distributed object resources requested by a client application for a global transaction as being updateable and committable by either a single-phase, two-phase, or mixed-phase protocol, wherein the object resources are distributed among a plurality of servers including the first server, wherein at least one of the plurality of servers has a transaction manager supporting a single-phase commit protocol, and wherein at least one other of the plurality of servers has a transaction manager supporting a two-phase commit protocol; and

the transaction manager on the first server selectively attempting to commit the registered resources using either the single-phase, two-phase or mixed-phase commit protocol in accordance with the results of the registration step, wherein the transaction manager attempting to commit a registered resource using the mixed-phase commit protocol comprises the steps of;

preparing to commit all resources registered as updateable and committable by the two-phase protocol;

attempting to commit all resources registered as updateable and committable by the single-phase protocol;

rolling-back any resources registered as updateable and committable by the single-phase commit protocol and any resources registered as updateable and committable by the two-phase commit protocol if the attempt to commit a resource registered as updateable and committable by the single-phase protocol was unsuccessful; and

attempting to commit all resources registered as updateable and committable by the two-phase commit protocol if the attempt to commit all resources registered as updateable and committable by the single-phase protocol was successful.

2. The method of claim 1, further comprising the following steps of:

preceding the selective registration step, and responsive to the first server in the distributed object-oriented transaction processing environment receiving the client application'"'"'s request for a global transaction involving the distributed object resources, designating the first server'"'"'s transaction manager as root transaction manager and each other server'"'"'s transaction manager as a subordinate transaction manager;

preceding the selective registration step, determining what commit procedure is supported by the root transaction manager and each subordinate transaction manager;

the root transaction manager performing the selective registration step in accordance with the determination of what commit procedure is supported by the root transaction manager and each of the subordinate transaction managers; and

the root transaction manager selectively implementing either a single-phase, two-phase, or mixed-phase commit procedure for each object resource registered in the global transaction in accordance with how the resources are registered in the registration step.

3. The method of claim 1, wherein the step of registering object resources includes the step of a determination by the root transaction manager of which client application requested resources are allowed to participate in the global transaction, based on configuration information provided by a system administrator defining which commit procedure to use.

4. The method of claim 2, wherein the step of registering object resources includes the step of a determination by the root transaction manager of which client application requested resources are allowed to participate in the global transaction, based on configuration information provided by a system administrator defining which commit procedure to use.

5. The method of claim 4, wherein if the configuration information indicates a single-phase commit procedure is to be used, then each object resource requested by the client application is allowed to participate in the global transaction and is registered as being committable by a single-phase commit procedure.

6. The method of claim 4, wherein if the configuration information indicates a two-phase commit procedure is to be used, then any object resource requested by the client application that is supported by a two-phase commit protocol is allowed to participate in the global transaction by the root transaction manager and is registered as being committable by a two-phase commit procedure, while any requested object resource supported by a single-phase commit protocol is not allowed to participate in the global transaction by the root transaction manager.

7. The method of claim 4, wherein if the configuration information indicates a mixed-phase commit procedure is to be used, then any object resource requested by the client application is allowed to participate, and is registered as being committable by a mixed-phase commit procedure.

8. The method of claim 4, wherein if the participating object resources in the global transaction are registered as being committable by a single-phase commit procedure, then further comprising the step of the root transaction manager implementing a single-phase commit procedure for committing each participating object resource.

9. The method of claim 4, wherein if the object resources participating in the global transaction are registered as being committable by a two-phase commit procedure, then further comprising the step of the root transaction manager implementing a two-phase commit procedure for committing each object resource registered as being committable by a two-phase commit procedure.

10. The method of claim 4, wherein if the object resources participating in the global transaction are registered as being committable by a mixed-phased commit procedure, then further comprising the steps of:

the root transaction manager preparing all object resources being supported by a two-phase commit procedure;

the root transaction manager committing all object resources being supported by a single-phase commit procedure; and

the root transaction manager committing all object resources being supported by a two-phase commit procedure.

11. The method of claim 5, wherein if the participating object resources in the global transaction are registered as being committable by a single-phase commit procedure, then further comprising the step of the root transaction manager implementing a single-phase commit procedure for committing each participating object resource.

12. The method of claim 6, wherein if the object resources participating in the global transaction are registered as being committable by a two-phase commit procedure, then further comprising the step of the root transaction manager implementing a two-phase commit procedure for committing each object resource registered as being committable by a two-phase commit procedure.

13. The method of claim 7, wherein if the object resources participating in the global transaction are registered as being committable by a mixed-phased commit procedure, then further comprising the steps of:

the root transaction manager preparing all object resources being supported by a two-phase commit procedure;

the root transaction manager committing all object resources being supported by a single-phase commit procedure; and

the root transaction manager committing all object resources being supported by a two-phase commit procedure.

14. A system for supporting a plurality of different commit procedures in a distributed object-oriented transaction processing environment including a plurality of server computers over which objects are distributed and at least one client application, the system comprising:

a server computer denominated as the root server having a processing unit coupled with main memory and further coupled with storage; and

a transaction manager operating in the main memory of the root server that is configured for communicating with the processing unit to perform the computer-executed steps, all performed within a single transaction commit cycle, of;

selectively registering distributed object resources requested by a client application for a global transaction as being updateable and committable by either a single-phase, two-phase, or mixed-phase protocol, wherein the object resources are distributed among the plurality of server computers including the root server, wherein at least one of the plurality of servers has a transaction manager supporting a single-phase commit protocol, and at least one other of the plurality of servers has a transaction manager supporting a two-phase commit protocol; and

the transaction manager on the root server selectively attempting to commit the registered resources using either the single-phase, two-phase or mixed-phase commit protocol in accordance with the results of the registration step, wherein the transaction manager attempting to commit a registered resource using the mixed-phase commit protocol comprises the steps of;

preparing to commit all resources registered as updateable and committable by the two-phase protocol;

attempting to commit all resources registered as updateable and committable by the single-phase protocol;

rolling-back any resources registered as updateable and committable by the single-phase commit protocol and any resources registered as updateable and committable by the two-phase commit protocol if the attempt to commit a resource registered as updateable and committable by the single-phase protocol was unsuccessful; and

attempting to commit all resources registered as updateable and committable by the two-phase commit protocol if the attempt to commit all resources registered as updateable and committable by the single-phase protocol was successful.

15. The system of claim 14, wherein preceding the selective registration step, and responsive to the root server in the distributed object-oriented transaction processing environment receiving the client application'"'"'s request for a global transaction involving the distributed object resources, denominating the root server'"'"'s transaction manager as root transaction manager and each other server'"'"'s transaction manager as a subordinate transaction manager, and the root transaction manager is further configured for performing the computer-executed steps of:

preceding the selective registration step, determining what commit procedure is supported by the root transaction manager and each subordinate transaction manager;

performing the selective registration step in accordance with the determination of what commit procedure is supported by the root transaction manager and each of the subordinate transaction managers; and

selectively implementing either a single-phase, two-phase, or mixed-phase commit procedure for each object resource registered in the global transaction in accordance with how the resources are registered in the registration step.

16. The system of claim 15, wherein the root transaction manager is configured for performing the step of registering object resources by including the step determining which client application requested resources are allowed to participate in the global transaction, based on configuration information provided by a system administrator defining what commit procedure to use.

17. The system of claim 16, wherein if the configuration information indicates a single-phase commit procedure is to be used, then the root transaction manager is further configured for performing the computer-executed steps of allowing each object resource requested by the client application to participate in the global transaction and registering each participating object resource as being committable by a single-phase commit procedure.

18. The system of claim 16, wherein if the configuration information indicates a two-phase commit procedure is to be used, then the root transaction manager is further configured for performing the computer-executed steps of allowing any object resource requested by the client application that is supported by a two-phase commit protocol to participate in the global transaction, and registering each participating object resource as being committable by a two-phase commit procedure, while any requested object resource supported by a single-phase commit protocol is not allowed to participate in the global transaction by the root transaction manager.

19. The system of claim 16, wherein if the configuration information indicates a mixed-phase commit procedure is to be used, then the root transaction manager is further configured for performing the computer-executed steps of allowing any object resource requested by the client application to participate, and registering each participating object resource as being committable by a mixed-phase commit procedure.

20. The system of claim 16, wherein if the participating object resources in the global transaction are registered as being committable by a single-phase commit procedure, then the root transaction manager is further configured for performing the computer-executed step of implementing a single-phase commit procedure for committing each participating object resource.

21. The system of claim 16, wherein if the participating object resources in the global transaction are registered as being committable by a two-phase commit procedure, then the root transaction manager is further configured for performing the computer-executed step of implementing a two-phase commit procedure for committing each object resource registered as being committable by a two-phase commit procedure.

22. An apparatus for supporting a plurality of different commit procedures in a distributed object-oriented transaction processing environment including a plurality of server computers over which objects are distributed and at least one client application, comprising:

a first server computer including a processing unit;

a main memory for executing a computer program that is in communication with the processing unit; and

transaction manager logic operating in main memory of the first server and an object transaction service module that further includes a registration module and a commit module, wherein the registration module includes computer-executable logic that enables it to selectively register distributed object resources requested by a client application for a global transaction as being updateable and committable by either a single-phase, two-phase, or mixed-phase protocol, wherein the object resources are distributed among the plurality of servers including the first server, wherein at least one of the plurality of servers has a transaction manager supporting a single-phase commit protocol, and at least one other of the plurality of servers has a transaction manager supporting a two-phase commit protocol; and

the commit module includes computer-executable logic for selectively committing the registered resources in accordance with the results of the registration step, wherein the computer-executable logic for committing a resource registered as updateable and committable by the mixed-phase commit protocol comprises;

computer-executable logic for preparing to commit all resources registered as updateable and committable by the two-phase protocol;

computer-executable logic for attempting to commit all resources registered as updateable and committable by the single-phase protocol;

computer-executable logic for rolling-back any resources registered as committable by the single-phase commit protocol and any resources registered as updateable and committable by the two-phase commit protocol if the attempt to commit a resource registered as updateable and committable by the single-phase protocol was unsuccessful; and

computer-executable logic for attempting to commit all resources registered as updateable and committable by the two-phase commit protocol if the attempt to commit all resources registered as updateable and committable by the single-phase protocol was successful.

23. A program-product for use in a computer system for supporting a plurality of different commit procedures in a distributed object-oriented transaction processing environment including a plurality of server computers over which objects are distributed and at least one client application, comprising:

a registration module that selectively registers distributed object resources requested by a client application for a global transaction as being updateable and committable by either a single-phase, two-phase, or mixed-phase protocol, wherein the registration module is executed on the computer system, wherein the object resources are distributed among the plurality of servers including the first server, wherein at least one of the plurality of servers has a transaction manager supporting a single-phase commit protocol, and at least one other of the plurality of servers has a transaction manager supporting a two-phase commit protocol;

a commit module that selectively commits the registered resources in accordance with the results of the registration step when the commit module is executed on the computer system; and

signal-bearing media, bearing the registration and commit modules;

wherein the commit module commits each resource registered as updateable and committable by the mixed-phase commit by, as a first step, preparing to commit all resources registered as updateable and committable by the two-phase protocol;

wherein the commit module commits each resource registered as updateable and committable by the mixed-phase commit by, as a second step, attempting to commit all resources registered as updateable and committable by the single-phase protocol;

wherein the commit module commits each resource registered as updateable and committable by the mixed-phase commit by, as a third step, rolling-back any resources registered as updateable and committable by the single-phase commit protocol and any resources registered as updateable and committable by the two-phase commit protocol if the attempt to commit a resource registered as updateable and committable by the single-phase protocol was unsuccessful; and

wherein the commit module commits each resource registered as updateable and committable by the mixed-phase commit by, as a fourth step, attempting to commit all resources registered as updateable and committable by the two-phase commit protocol if the attempt to commit all resources registered as updateable and committable by the single-phase protocol was successful.