DISTRIBUTED TRANSACTIONAL RECOVERY SYSTEM AND METHOD

• US 20100169284A1
• Filed: 12/31/2008
• Published: 07/01/2010
• Est. Priority Date: 12/31/2008
• Status: Active Grant

• Current Assignee: SAP SE
• Original Assignee: SAP AG (SAP SE)
• Inventors: Walter, Thomas H., Peshev, Peter H., Tankov, Nikolai D., Kuersch, Ralf
• Granted Patent: US 9,417,977 B2
• Time in Patent Office: Days
• US Class Current: 707/682
• CPC Class Codes: G06F 11/1474 in transactions G06F16/20 takes precedence
• CPC Class Codes: G06F 11/2025 using centralised failover control functionality
• CPC Class Codes: G06F 11/2033 switching over of hardware resources
• CPC Class Codes: G06F 11/2035 without idle spare hardware

Abstract

In one embodiment the present invention includes a system for transaction recovery in a distributed computing environment. The system includes a transaction log server, application servers, and resource servers. The transaction log server stores a shared transaction log. The application servers implement a distributed transaction application and accesses the shared transaction log when performing a transaction using the distributed transaction application. The resource servers store data and that operate with the application servers to access the data according to the transaction. If one of the application servers fails, another application server assumes responsibility for a portion of the shared transaction log that was previously accessed by the failed application server.

Claims

1. A system for transaction recovery in a distributed computing environment, comprising:

a transaction log server that stores a shared transaction log;

a plurality of application servers that implements a distributed transaction application and that accesses the shared transaction log when performing a transaction using the distributed transaction application; and

a plurality of resource servers that stores data and that operates with the plurality of application servers to access the data according to the transaction,

wherein the plurality of application servers, the plurality of resource servers, and the transaction log server are implemented by a plurality of hardware devices that are connected via a network, and

wherein if an application server of the plurality of application servers becomes a failed application server, an active application server assumes responsibility for a portion of the shared transaction log that was previously accessed by the failed application server.

2. The system of claim 1, wherein the transaction log server includes one of a file system and a database management system.

3. The system of claim 1, wherein an application server of the plurality of application servers comprises:

a transaction manager that executes the transaction; and

a pending transaction list processor that accesses the shared transaction log.

4. The system of claim 1, wherein a first application server of the plurality of application servers comprises:

a pending transaction list processor that accesses a first portion of the shared transaction log corresponding to the first application server, and that accesses the portion of the shared transaction log that was previously accessed by the failed application server.

5. The system of claim 1, wherein the shared transaction log includes a plurality of logical transaction logs, wherein each of the plurality of logical transaction logs are associated with a corresponding one of the plurality of application servers and a corresponding run identifier.

6. The system of claim 1, wherein an application server of the plurality of application servers comprises:

a pending transaction list that stores a plurality of pending transactions;

a pending transaction list processor that accesses the shared transaction log and the pending transaction list.

7. The system of claim 1, wherein an application server of the plurality of application servers comprises:

a victim for deletion list that stores entries to be deleted from the shared transaction log; and

a transaction manager that adds a completed transaction from the shared transaction log to the victim for deletion list when the transaction manager has completed the completed transaction, and that deletes the entries in the victim for deletion list from the shared transaction log when the victim for deletion list reaches a defined size.

8. The system of claim 1, wherein an application server of the plurality of application servers comprises:

a transaction manager that performs a group update to the shared transaction log.

9. A computer-implemented method of transaction recovery in a distributed computing environment, comprising:

storing, with a transaction log server, a shared transaction log;

implementing, with a plurality of application servers, a distributed transaction application that accesses the shared transaction log when performing a transaction using the distributed transaction application; and

storing, with a plurality of resource servers, data, wherein the plurality of resource servers operates with the plurality of application servers to access the data according to the transaction,

wherein the plurality of application servers, the plurality of resource servers, and the transaction log server are implemented by a plurality of hardware devices that are connected via a network, and

wherein if an application server of the plurality of application servers becomes a failed application server, an active application server assumes responsibility for a portion of the shared transaction log that was previously accessed by the failed application server.

10. The computer-implemented method of claim 9, wherein the shared transaction log includes a plurality of logical transaction logs, wherein each of the plurality of logical transaction logs are associated with a corresponding one of the plurality of application servers and a corresponding run identifier.

11. The computer-implemented method of claim 9, wherein an application server of the plurality of application servers comprises:

a pending transaction list that stores a plurality of pending transactions;

a pending transaction list processor that accesses the shared transaction log and the pending transaction list.

12. The computer-implemented method of claim 9, wherein an application server of the plurality of application servers comprises:

a victim for deletion list that stores entries to be deleted from the shared transaction log; and

a transaction manager that adds a completed transaction from the shared transaction log to the victim for deletion list when the transaction manager has completed the completed transaction, and that deletes the entries in the victim for deletion list from the shared transaction log when the victim for deletion list reaches a defined size.

13. The computer-implemented method of claim 9, wherein an application server of the plurality of application servers comprises:

a transaction manager that performs a group update to the shared transaction log.

14. A computer program embodied on a plurality of tangible storage media, comprising:

a shared transaction log, stored by a transaction log server;

a distributed transaction application, stored by a plurality of application servers, that accesses the shared transaction log when performing a transaction; and

data, stored by a plurality of resource servers, that is accessed by the distributed transaction application according to the transaction,

wherein the plurality of application servers, the plurality of resource servers, and the transaction log server are implemented by a plurality of hardware devices that are connected via a network, and

wherein if an application server of the plurality of application servers becomes a failed application server, an active application server assumes responsibility for a portion of the shared transaction log that was previously accessed by the failed application server.

15. The computer program of claim 14, wherein the shared transaction log includes a plurality of logical transaction logs, wherein each of the plurality of logical transaction logs are associated with a corresponding one of the plurality of application servers and a corresponding run identifier.

16. The computer program of claim 14, wherein an application server of the plurality of application servers comprises:

a pending transaction list that stores a plurality of pending transactions;

a pending transaction list processor that accesses the shared transaction log and the pending transaction list.

17. The computer program of claim 14, wherein an application server of the plurality of application servers comprises:

a victim for deletion list that stores entries to be deleted from the shared transaction log; and

a transaction manager that adds a completed transaction from the shared transaction log to the victim for deletion list when the transaction manager has completed the completed transaction, and that deletes the entries in the victim for deletion list from the shared transaction log when the victim for deletion list reaches a defined size.

18. The computer program of claim 14, wherein an application server of the plurality of application servers comprises:

a transaction manager that performs a group update to the shared transaction log.