Database Contention and Deadlock Detection and Reduction Within Application Servers

• US 20080288682A1
• Filed: 07/29/2008
• Published: 11/20/2008
• Est. Priority Date: 03/31/2005
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Minshall, Robbie John, Laonipon, Bert Vincent, Rangaswamy, Srinvasan K., Norton, Carolyn Haibt
• Granted Patent: US 8,041,686 B2
• Time in Patent Office: Days
• US Class Current: 710/104
• CPC Class Codes: G06F 11/3442 for planning or managing the needed capacity
• CPC Class Codes: G06F 11/3447 Performance evaluation by modeling
• CPC Class Codes: G06F 9/485 Task life-cycle, e.g. stopping, restarting, resuming execution G06F9/4881 takes precedence
• CPC Class Codes: G06F 9/52 Program synchronisation; Mutual exclusion, e.g. by means of semaphores
• CPC Class Codes: Y10S 707/99938 Concurrency, e.g. lock management in shared database
• CPC Class Codes: Y10S 707/99953 Recoverability

Abstract

A method in a data processing system for detecting and reducing database contention and deadlock caused from within an application server. A determination is made as to whether a set of parameters in a statistical model indicates contention. If the set of parameters in the statistical model indicates contention, an application server administrator is notified of the contention and the number of threads in an application server pool is reduced. If the set of parameters in the statistical model indicates contention is reduced, the number of threads in the application server pool is increased.

Claims

1-11. -11. (canceled)

12. A data processing system for detecting and reducing database contention caused from within an application server, the data processing system comprising:

a bus system;

a memory connected to the bus system, wherein the memory includes computer usable program code; and

a processing unit connected to the bus system, wherein the processing unit executes the computer usable program code to determine if a set of parameters in a statistical model indicates contention, wherein the statistical model includes a parameter for level and type of workload;

responsive to determining the set of parameters in the statistical model indicates contention, reduce a number of threads in an application server pool;

establish whether the set of parameters in the statistical model indicates contention is reduced for a specified period of continuous time;

responsive to establishing the set of parameters in the statistical model does not indicate contention is reduced for the specified period of continuous time, return to the reducing step;

responsive to establishing the set of parameters in the statistical model indicates contention is reduced for the specified period of continuous time, increase the number of threads in the application server pool;

verify whether the number of threads is less than a normal number of threads;

responsive to verifying the number of threads is not less than the normal number of threads, return to the determining step;

responsive to verifying the number of threads is less than the normal number of threads, resolve if the set of parameters in the statistical model indicates contention;

responsive to resolving the set of parameters in the statistical model indicates contention, return to the reducing step; and

responsive to resolving the set of parameters in the statistical model does not indicate contention, return to the increasing step.

14. The data processing system of claim 12 wherein the processing unit executes the computer usable program code to, responsive to reducing the number of threads in the application server pool, notify the application server administrator.

15. The data processing system of claim 12, wherein the processing unit executes the computer usable program code to determine if a set of trends involving parameters in the statistical model indicates contention instead of determining if the set of parameters in the statistical model indicates contention.

16. The data processing system of claim 12 wherein the statistical model includes a parameter for thread pool use.

17. The data processing system of claim 12 wherein the statistical model includes a parameter for time spent waiting for a thread to be assigned.

18. The data processing system of claim 12 wherein the statistical model includes a parameter for a number of time-outs.

19. The data processing system of claim 12 wherein the statistical model includes a parameter for time spent waiting for a response.

13. (canceled)

20. A computer program product on a recordable-type medium for use in a data processing system for detecting and reducing database contention caused from within an application server, the computer program product comprising:

first instructions for determining if a set of parameters in a statistical model indicates contention, wherein the statistical model includes a parameter for level and type of workload;

responsive to determining the set of parameters in the statistical model indicates contention, second instructions for reducing a number of threads in an application server pool;

third instructions for establishing whether the set of parameters in the statistical model indicates contention is reduced for a specified period of continuous time;

responsive to establishing the set of parameters in the statistical model does not indicate contention is reduced for the specified period of continuous time, fourth instructions for returning to the reducing step;

responsive to establishing the set of parameters in the statistical model indicates contention is reduced for the specified period of continuous time, fifth instructions for increasing the number of threads in the application server pool;

sixth instructions for verifying whether the number of threads is less than a normal number of threads;

responsive to verifying the number of threads is not less than the normal number of threads, seventh instructions for returning to the determining step;

responsive to verifying the number of threads is less than the normal number of threads, eighth instructions for resolving if the set of parameters in the statistical model indicates contention;

responsive to resolving the set of parameters in the statistical model indicates contention, ninth instructions for returning to the reducing step; and

responsive to resolving the set of parameters in the statistical model does not indicate contention, tenth instructions for returning to the increasing step.