Method and system for minimizing loss in a computer application

• US 20060020858A1
• Filed: 07/18/2005
• Published: 01/26/2006
• Est. Priority Date: 07/20/2004
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Softricity Inc (Microsoft Corporation)
• Inventors: Schaefer, Stuart
• Granted Patent: US 7,426,661 B2
• Time in Patent Office: Days
• US Class Current: 714/38
• CPC Class Codes: G06F 11/0715 in a system implementing multitasking multitasking per se G06F9/46
• CPC Class Codes: G06F 11/0793 Remedial or corrective actions recovery from an exception in an instruction pipeline G06F9/3861; by retry G06F11/1402; for recovering from a failure of a protocol instance or entity H04L69/40
• CPC Class Codes: G06F 11/1438 Restarting or rejuvenating
• CPC Class Codes: G06F 11/1482 by means of middleware or OS functionality

Abstract

During the execution of a software application, a user will often create significant data representing the work they are trying to accomplish. Additionally, the act of using the application will create states within that program reflecting the operations performed during use. In many scenarios, this data can be lost through application, system, or network failure. The present invention provides a means for resilience through (a) redirection of program execution in response to failure onto known code paths representing save and/or exit from the program, (b) suspension of the program and restoration after the fault has been repaired, and (c) snapshot of the application state for restoration after the application failure.

Claims

1. A method for minimizing loss of data while using a computer application comprising the steps of:

monitoring the computer application to detect the presence of a fault or potential fault;

selecting a method for handling the fault or potential fault; and

performing the selected method for handling the fault or potential fault;

wherein the steps of monitoring, selecting and performing are carried out without access to or modification of the code for the computer application.

2. The method of claim 1 wherein the method for handling the fault or potential fault is selected from the following methods:

redirecting execution of code of the computer application;

suspending the computer application; and

taking a memory snapshot of the computer application.

3. The method of claim 1 wherein the step of performing the selected method for handling the fault or potential fault comprises invoking save logic of the computer application in order to save data.

4. The method of claim 1 wherein the step of performing the selected method for handling the fault or potential fault comprises

suspending the computer application;

monitoring the computer application for an indication that resumption can occur; and

selecting one of resuming the computer application or resetting to a program counter of the computer application.

5. The method of claim 1 wherein the step of performing the selected method for handling the fault or potential fault further comprises:

suspending the computer application;

taking a memory snapshot of the computer application; and

storing the memory snapshot in non-volatile storage means.

6. The method of claim 1 wherein the step of monitoring the computer application comprises

intercepting a call to the computer application;

inspecting results of the call; and

selecting whether to return control back to the computer application or to select a method for handling the fault or potential fault.

7. The method of claim 1 wherein the step of monitoring a computer application comprises monitoring internal operations of the computer application.

8. The method of claim 1 wherein the step of monitoring a computer application comprises monitoring external events.

9. The method of claim 1 wherein the step of handling the fault or potential fault comprises communicating with a user of the computer application regarding the fault or potential fault.

32. The method of claim 1 further comprising analyzing code of the computer application to identify common entry points.

33. The method of claim 32 wherein the step of analyzing the code to identify common entry points comprises tracing the application during its execution.

10. A method for minimizing loss of data while using a computer application comprising:

monitoring a computer application to detect the presence of a fault or potential fault; and

invoking save logic of the computer application in response to the detection of the presence of a fault or potential fault in order to save data.

11. The method of claim 10 wherein the step of invoking save logic of the computer application comprises directly calling the computer application save entry point.

12. The method of claim 10 wherein the step of invoking save logic of the computer application comprises resetting a program counter of the computer application to a save entry point.

13. The method of claim 10 wherein the step of invoking save logic of the computer application comprises inserting jump instructions in the live code stream to force call of a save.

14. The method of claim 10 wherein the step of invoking save logic of the computer application comprises redirecting the computer application to a local data source or proxy store.

15. The method of claim 10 further comprising recording the fault or potential fault internally in the system running the computer application.

16. The method of claim 10 further comprising forwarding a fault notification to an external monitoring system.

17. The method of claim 10 further comprising communicating with a user of the computer application regarding the fault or potential fault.

18. The method of claim 17 wherein the step of communicating with a user of the computer application regarding the fault or potential fault comprises asking the user if it wants the fault or potential fault to be handled or whether the fault or potential fault should be allowed to occur.

19. A method for minimizing loss of data while using a computer application comprising:

monitoring a computer application to detect the presence of a fault or potential fault;

suspending the computer application in response to detection of a fault or potential fault;

monitoring the computer application for an indication that resumption can occur; and

selecting to either resume the computer application or reset to a program counter of the computer application.

20. The method of claim 19 further comprising preventing unwanted resumption of the computer application while the computer application is suspended.

21. The method of claim 19 wherein the step of preventing unwanted resumption of the computer application comprises making the computer application controllable only through predetermined means.

22. The method of claim 19 further comprising the step of saving a state of the computer application as a series of side effects.

23. The method of claim 19 further comprising the step of saving a state of the computer application though communication with an external system.

24. The method of claim 19 wherein the computer application is suspended for the duration of a detected fault.

25. The method of claim 19 wherein the step of suspending the computer application comprises the step of communicating with a user via a user interface to determine whether the user wishes to have the computer application suspended in anticipation of a faulty state.

26. A method for minimizing loss of data while using a computer application comprising:

suspending a computer application in response to the presence of a fault or potential fault in the computer application;

taking a memory snapshot of the application; and

storing the memory snapshot to an auxiliary memory device.

27. The method of claim 26 further comprising

terminating the computer application after the memory snapshot is stored and

on invocation, either restoring the computer application or allowing another instance of the computer application to be created.

28. The method of claim 27 wherein the stored memory snapshot is recoverable after termination of the computer application.

29. The method of claim 26 further comprising preventing the computer application from being invoked after suspension of the computer application until a detected fault or potential fault is cleared or explicitly confirmed by a user.

30. The method of claim 26 wherein the step of restoring the computer application comprises mapping memory of the computer application and resetting internal operating system kernel data structures.

31. The method of claim 26 further comprising the steps of restoring an external connection to a computer on which the computer application is used in response to detection of a fault that the external connection is disconnected.