Method and apparatus for preventing overload using scaled recovery

• US 20020147835A1
• Filed: 04/04/2001
• Published: 10/10/2002
• Est. Priority Date: 04/04/2001
• Status: Active Grant

• Current Assignee: Longhorn Automotive Group LLC (Alpha Alpha Intellectual Partners LLC)
• Original Assignee: Hall Aluminum LLC (Intellectual Ventures LLC)
• Inventors: Zatloukal, Peter, Shefner, David Byron
• Granted Patent: US 7,240,117 B2
• Time in Patent Office: Days
• US Class Current: 709/237
• CPC Class Codes: H04L 67/62 Establishing a time schedule for servicing the requests
• CPC Class Codes: H04L 69/28 Timers or timing mechanisms used in protocols
• CPC Class Codes: H04L 69/329 in the application layer [OSI layer 7]
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

In the scaled recovery system of the present invention, clients delay for an additional period of time prior to attempting to access a previously unavailable resource that has since become available, rather than accessing the shared resource at full speed once an initial back off interval is over. Through the continual increment and decrement of client back off intervals, the present invention provides dynamic tuning of overall system load in the case of overloaded shared resources.

Claims

1. In a client, a method comprising:

attempting to access a shared resource;

detecting that the shared resource is unavailable;

determining a first back off interval for the client to delay before reattempting to access the shared resource;

successfully accessing the shared resource upon expiration of the first back off interval; and

determining a second back off interval for the client to delay before reattempting to access the shared resource after said successful access.

2. The method of claim 1, wherein said second back off interval is less in duration than said first back off interval.

3. The method of claim 2, further comprising:

successively determining additional back off intervals upon each successful access of the shared resource by the client, each of said successive back off intervals being less in duration than each previous back off interval.

4. The method of claim 1, wherein said second back off interval is determined independent of whether the shared resource is available.

5. The method of claim 1, wherein said attempting to access a shared resource comprises attempting to access a server device coupled to the client.

6. The method of claim 1, wherein said attempting to access a shared resource further comprises attempting to access a shared network.

7. The method of claim 6, wherein said shared network further comprises an Ethernet network.

8. The method of claim 6, wherein said shared network further comprises a wireless network.

9. The method of claim 1, wherein said attempting to access a shared resource further comprises attempting to access a data bus.

10. An apparatus comprising:

a storage medium having stored therein a plurality of programming instructions for facilitating a client in attempting to access a shared resource, detecting that the shared resource is unavailable, determining a first back off interval for the client to delay before reattempting access to the shared resource, successfully accessing the shared resource upon expiration of the first back off interval, and determining a second back off interval for the client to delay before reattempting access to the shared resource after said successful access; and

one or more processors coupled to the storage medium to execute the programming instructions.

11. The apparatus of claim 10, wherein said second back off interval is less in duration than said first back off interval.

12. The apparatus of claim 11, further comprising:

programming instructions to further facilitate the client in successively determining additional back off intervals upon each successful access of the shared resource by the client, each of said successive back off intervals being less in duration than each previous back off interval.

13. The apparatus of claim 10, wherein said second back off interval is determined independent of whether the shared resource is available.

14. The apparatus of claim 10, wherein said shared resource comprises a server device coupled to the client.

15. The apparatus of claim 10, wherein said shared resource comprises a shared network.

16. The apparatus of claim 15, wherein said shared network comprises an Ethernet network.

17. The apparatus of claim 15, wherein said shared network comprises a wireless network.

18. The apparatus of claim 10, wherein said shared resource comprises a data bus.

19. The apparatus of claim 10, further comprising:

a counter to determine how many unsuccessful access attempts of the shared resource have been made by the client, wherein the counter value is not reset to zero upon the client successfully accessing the shared resource.

20. A machine accessible medium having stored therein a plurality of programming instructions for facilitating a client in attempting to access a shared resource, detecting that the shared resource is unavailable, determining a first back off interval for the client to delay before reattempting access to the shared resource, successfully accessing the shared resource upon expiration of the first back off interval, and determining a second back off interval for the client to delay before reattempting access to the shared resource after said successful access.

21. In a client, a method comprising:

detecting that a shared resource is unavailable;

determining a first time period for the client to delay before attempting to access the shared resource;

upon expiration of the first time period, determining a new first time period for the client to delay before attempting to access the shared resource if the shared resource remains unavailable, and determining a second time period for the client to delay before reattempting to access the shared resource after the successful access of the shared resource by the client.