Unilaterally-controlled, time-insensitive, data-link recovery apparatus and method

• US 5,835,698 A
• Filed: 09/20/1996
• Issued: 11/10/1998
• Est. Priority Date: 09/20/1996
• Status: Expired due to Term

• Current Assignee: Micro Focus Software, Inc. (Open Text Corporation)
• Original Assignee: Novell Incorporated (Open Text Corporation)
• Inventors: Harris, Jack C., Mahlum, David J.
• Primary Examiner(s): PALYS, JOSEPH E
• Application Number:
  US08/717,486
• Time in Patent Office: 781 Days
• Field of Search: 395/182.02, 395/182.13, 395/182.16, 395/105.01, 395/185.1, 395/200.12, 395/200.16, 395/182.14, 395/182.15, 395/182.18, 395/182.09, 395/569, 395/183.02, 364/266.5, 364/266.6
• US Class Current: 714/15
• 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: H04L 41/0654 using network fault recovery ring fault isolation or reconfiguration in loop networks without recovery actions by a network management system H04L12/437

Abstract

An apparatus and method for unilaterally-controlled, time-insensitive recovery of disconnected data links provides for user-transparent recovery, without requiring inputs from a user or other intervention. Data and executable operations may be preserved, as re-booting is not required. Optionally, opportunity for user intervention may be provided, at a user'"'"'s request. Recovery may occur automatically by use of expert knowledge applied to reported system errors from the disconnected communication link. An apparatus may rely on a logical device within an actuator or machine of mechanical, pneumatic, hydraulic, electrical or electronic character. A task to be reported to an actuator as successful or failed, may be internal to the actuator, internal to the logical device, or external to both. Data structures stored in a memory device, may implement the invention readily from within an application running on a processor in a computer. Information (data, operational steps) may be preserved at an atomic level of granularity.

Claims

1. An apparatus comprising:

an actuator comprising a signal generator effective to provide a task initiation signal;

a communication link operably connecting the actuator to a task executing device;

the task executing device adapted to receive the task initiation signal, to execute a task in response thereto, and to return a failure signal in the event of a failure of the task executing device to complete the task;

a logical device operably associated with the actuator, the logical device being adapted to receive the failure signal, automatically select for the actuator a preferred recovery response to the failure signal, and to communicate an instruction signal to the actuator effective to execute the preferred recovery response independent of the time elapsed after the failure; and

a memory device operably connected to the actuator, for storing data structures, the data structures comprising;

a first data set corresponding to execution of the task prior to the failure signal,

a second data set corresponding to the task executed after the recovery response, and

each of the first and second data sets being partitioned at an atomic level, independent from redundancies, checkpoints, rollbacks, conversations, and backwards recoveries.

2. The apparatus of claim 1 wherein the instruction signal corresponds to continuing execution of the task by the task executing device from a step corresponding to the return of the failure signal.

3. The apparatus of claim 2 further comprising a user input device operably connected to the logical device to selectively receive a user input directing the logical device.

4. The apparatus of claim 3 wherein the user input device provides a user signal effective to initiate an interactive exchange of information between the logical device and a user.

5. The apparatus of claim 4 wherein the user input device is adapted to receive instructions from a user corresponding to selective feedback from the task executing device and selective control of the preferred recovery response.

6. The apparatus of claim 3 further comprising a user output device operably connected to the logical device to selectively provide feedback to a user, the feedback indicating the desirability of potential inputs available to a user to send to the logical device.

7. The apparatus of claim 1 wherein the logical device is programmed to automatically continue the task from a condition existing at the occurrence of the failure.

8. The apparatus of claim 1 wherein the selection of a preferred recovery response is independent of the time elapsed after the failure.

9. The apparatus of claim 1 wherein the task executing device and the logical device comprise at least one general purpose digital computing device, and the outcome of the selection of a preferred recovery response is independent from the general purpose digital computing device.

10. The apparatus of claim 1 wherein the logical device selects the preferred recovery path unilaterally with respect to the task executing device.

11. The apparatus of claim 1 wherein the logical device comprises a general purpose computing device having a processor hosting an application, and in which the logical device is programmed into the application to run on the processor, independent of protocols in layers below an application layer level.

12. The apparatus of claim 1 wherein the preferred recovery response comprises a recovery path comprising recovery steps executed by the logical device, and wherein the selection of the preferred recovery response is based on providing a plurality of optional solutions, each with a corresponding heuristic solution analysis presented to a user by the logical device.

13. The apparatus of claim 12 wherein the logical device comprises an artificial intelligence engine to propose the preferred recovery response, and provide the heuristic solution analysis.

14. The apparatus of claim 1 wherein the logical device comprises an artificial intelligence engine to propose a preferred recovery response, and provide to a user a heuristic solution analysis.

15. The apparatus of claim 1, wherein the selection of, and an execution of, the preferred recovery response are executed transparently with respect to a user.

16. The apparatus of claim 1 wherein the task is a transfer of data over the communication link.

17. An apparatus comprising:

a communication link adapted to communicate data;

a processor operably connected to the communication link and programmed to run executables comprising

an application executable hosted on the processor and effective to transfer control of the processor to a task, the task being effective to cause a failure signal to indicate a failure of the task to execute completely, and

a recovery executable effective to recognize the failure signal, automatically select a recovery method, execute the selected recovery method, preserving a partial data set created by the task, partitioned at an atomic level, and reflecting the state of the task exactly prior to the failure, and cause completion of the task, beginning with executing a step corresponding to the failure independent of the time elapsed after the failure;

a first storage device operably connected to the communication link to store the partial data set corresponding to execution of a first portion of the task prior to the failure, and to store, independent from redundancies, checkpoints, rollbacks, conversations, and backwards recoveries, and after execution of the recovery method, a completion data set corresponding to a second portion of the task executed after the failure.

18. The apparatus of claim 17 further comprising an input device operably connected to selectively generate an interrupt signal in response to actuation of the input device by a user.

19. The apparatus of claim 17 further comprising an output device operably connected to the communication link to selectively provide to a user feedback corresponding to control of the recovery method.

20. The article of claim 17 further comprising an interrupt block storing data corresponding to an interrupt input by a user.

21. The article of claim 17 further comprising an artificial intelligence block storing an artificial intelligence executable effective to be loaded into the processor to automatically determine a preferred method to recover the task.

22. The article of claim 21 further comprising a user output block storing data corresponding to an analysis of the artificial intelligence executable, and effective to instruct a user regarding available options and associated desirabilities thereof in response to an interrupt input by a user.

23. An article comprising a memory device provided with blocks of memory adaptable to store executables and data, the memory device comprising:

a first block storing a task executable to be loaded to run on a processor operably connected to the memory device;

a second block storing an application, the application having integrated therein a recovery executable to be loaded to run on the processor upon a failure of the task executing device to complete execution of a task;

a third block persistently storing first data comprising each atomic unit of data generated by the task executing device, exclusively prior to the failure;

a fourth block storing second data generated by the task executable, exclusively after the failure, the first and second data corresponding together comprising a complete data set indistinguishable from a normal data set generated by the task executable executing the task normally without the failure; and

a recovery control data block comprising data containing an abort flag used by the recovery executable to recover the task after the failure and effective to disable all further attempts to execute recovery processes.

24. The article of claim 23, wherein the application contains an executable effective to invoke the task executable.

25. The article of claim 23 further comprising a shutdown executable block storing a shutdown executable within the application effective to direct execution of the recovery executable.

26. A method of auto-recovery of a task operating on a computer, the method comprising:

providing a processor for operating executables, the processor being operably connected by a datalink to a memory device for storing executables and data;

providing an application comprising a plurality of executables executable on the processor, the application also comprising an initiation executable effective to initiate a task executable and comprising a recovery executable effective to recover the task executable following a failure of the task executable to complete execution;

operating the application;

invoking the task executable, preserving first data generated during execution;

determining that a failure of the task executable has occurred;

invoking automatically the recovery executable to recover the task to a state existing at the time of the failure;

completing the task, generating second data, mutually exclusive of the first data, during execution thereof following the failure, the first and second data forming a non-redundant, complete data set, corresponding to, and indistinguishable from, a normal data set generated by the task operating without failure.

27. The method of claim 26 further comprising saving, at an atomic level recognized by the task executable, the first data generated by the task executable prior to the failure.

28. The method of claim 26 further comprising receiving an interrupt input by a user;

and

providing to a user a heuristic analysis of options to effect a recovery of the task after the failure, with an evaluation reflecting a desirability of each.

29. The method of claim 26 wherein the recovery executable is effective to recover the task independently from time elapsed after the failure.