Thread monitoring using shared memory

• US 20060143608A1
• Filed: 12/28/2004
• Published: 06/29/2006
• Est. Priority Date: 12/28/2004
• Status: Active Grant

• Current Assignee: SAP SE
• Original Assignee: SAP AG (SAP SE)
• Inventors: Dostert, Jan, Kilian, Frank, Petev, Petio, Fleischer, Christian, Werner, Randolf
• Granted Patent: US 7,689,989 B2
• Time in Patent Office: Days
• US Class Current: 718/1
• CPC Class Codes: G06F 11/3636 by tracing the execution of the program
• CPC Class Codes: G06F 2209/5018 Thread allocation
• CPC Class Codes: G06F 9/5027 the resource being a machine, e.g. CPUs, Servers, Terminals

Abstract

A system and method to monitor worker threads within a Java virtual machine. At least one program is executed on the Java virtual machine to perform a task. A worker thread of the Java virtual machine is assigned to perform the task. Status information for the worker thread is generated and reported into memory external to the Java virtual machine to enable monitoring of the worker thread from external to the Java virtual machine.

Claims

1. A computer-implemented method, comprising:

executing at least one program on a Java virtual machine (“

JVM”

) to perform a task;

assigning a worker thread to the task;

generating status information about the worker thread; and

reporting the status information into memory external to the JVM to enable monitoring of the worker thread from external to the JVM.

2. The method of claim 1, further comprising creating the worker thread with a class including at least one reporting method, the reporting method imparting reporting functionality to the worker thread, the reporting functionality to report the status information into the memory external to the JVM.

3. The method of claim 2, further comprising registering a reporting slot within the memory external to the JVM to store the status information about the worker thread.

4. The method of claim 3, further comprising registering a first plurality of reporting slots within the memory external to the JVM to store the status information about a corresponding first plurality of worker threads of the JVM.

5. The method of claim 4, wherein the memory external to the JVM comprises shared memory for monitoring other worker threads in other JVMs of an application server (“

AS”

) instance including the JVM, and further comprising;

reporting other status information about the other worker threads within the other JVMs of the AS instance.

6. The method of claim 4, wherein assigning the worker thread to the task comprises assigning the worker thread from a thread pool of available worker threads, and further comprising:

reporting an idle status into the memory external to the JVM for each of the available worker threads idle within the thread pool.

7. The method of claim 1, further comprising performing subtasks associated with the task, and wherein reporting the status information comprises reporting the status information in response to each of the subtasks to provide subtask related information within the status information.

8. The method of claim 7, wherein reporting the status information in response to each of the subtasks comprises reporting a first portion of the status information in response to each of the subtasks within a selectable reporting depth of the subtasks, while not reporting a second portion of the status information below the selectable reporting depth of the subtasks.

9. The method of claim 1, wherein the status information about the worker thread includes at least one of a thread state, a thread creation timestamp, a last thread update timestamp, a last task update timestamp, a last subtask update timestamp, a thread pool name, a class name, a thread name, a task name, a subtask name, and a username of a client originating a corresponding one of the work requests.

10. The method of claim 1, wherein the status information about the worker thread includes a call stack having an execution history of the worker thread.

11. The method of claim 1, further comprising:

retrieving the status information about the worker thread from the memory; and

transmitting the status information to a monitoring console to display the status information.

12. A machine-accessible medium that provides instructions that, if executed by a machine, will cause the machine to perform operations comprising:

executing tasks by at least two Java virtual machines (“

JVMs”

) within an application server (“

AS”

) instance to service work requests received by the AS instance;

assigning worker threads to the tasks to store placeholder information associated with each of the tasks;

generating status information about each of the worker threads; and

storing the status information about each of the worker threads into shared memory external to the JVMs during operation of the JVMs.

13. The machine-accessible medium of claim 12, further providing instructions that, if executed by the machine, will cause the machine to perform further operations, comprising:

creating each of the worker threads to include a reporting method, wherein the reporting method of each of the worker threads reports the status information of a corresponding one of the worker threads into the shared memory.

14. The machine-accessible medium of claim 13, further providing instructions that, if executed by the machine, will cause the machine to perform further operations, comprising:

registering a reporting slot within the shared memory for each of the worker threads, the reporting slot to store the status information corresponding to one of the worker threads.

15. The machine-accessible medium of claim 14, wherein generating the status information includes generating the status information while executing the tasks, and wherein storing the status information includes storing the status information in an interleaving manner with executing the tasks.

16. The machine-accessible medium of claim 12, wherein at least some of the tasks include subtasks, and wherein generating the status information for each of the worker threads comprises generating the status information about each of the worker threads assigned to one of the subtasks, and wherein storing the status information into the shared memory includes storing the status information about each of the worker threads in response to the subtasks.

17. A system, comprising:

a server node to execute an application server (“

AS”

) instance, the AS instance including logic executable by a processor of the server node to;

execute tasks by at least two Java virtual machines (“

JVMs”

) within the AS instance to service work requests received by the AS instance;

assign worker threads to the tasks to store placeholder information associated with each of the tasks;

generate status information about each of the worker threads; and

report the status information about each of the worker threads into shared memory external to the JVMs during operation of the JVMs.

18. The system of claim 17, wherein the worker threads each include reporting functionality to report the status information into the shared memory.

19. The system of claim 18, wherein the shared memory includes reporting slots to store the status information, each of the reporting slots to store only status information from one of the worker threads.

20. The system of claim 17, further comprising a client node to execute a management console, the management console including logic executable by a processor of the client node to:

send a status query to the server node;

receive the status information from the server node; and

display the status information in a user readable format.