Method, apparatus, and program for minimizing invalid cache notification events in a distributed caching environment

• US 20050160303A1
• Filed: 01/15/2004
• Published: 07/21/2005
• Est. Priority Date: 01/15/2004
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Martin, Brian Keith, Fricano, Charles Philip, Shupp, Daniel Christopher
• Granted Patent: US 7,318,165 B2
• Time in Patent Office: Days
• US Class Current: 713/600
• CPC Class Codes: G06F 12/0808 with cache invalidating means G06F12/0815 takes precedence
• CPC Class Codes: Y10S 707/99953 Recoverability
• CPC Class Codes: Y10S 707/99954 Version management

Abstract

A distributed cache management system that minimizes invalid cache notification events is provided. A cache management system in a sending device processes outgoing cache notification events by adding information about the source server'"'"'s clock. A cache management system in the receiving device then uses this information to adjust event information once the event is received.

Claims

1. A method for managing a cache in a distributed caching environment, the method comprising:

receiving a cache notification event from a sending device, wherein the cache notification event includes time relative information and a clock value for the sending device;

determining a clock delta by determining a difference between the local clock and the clock value of the sending device; and

adjusting the time relative information in the cache notification event based upon the clock delta.

2. The method of claim 1, further comprising:

validating the cache notification event.

3. The method of claim 2, further comprising:

discarding the cache notification event if the cache notification event is invalid.

4. The method of claim 1, wherein the cache notification event is one of an add event, an update event, and an invalidation event.

5. The method of claim 1, wherein the time relative information is an expiration value.

6. The method of claim 5, wherein the expiration value is one of a discrete time and an amount of time relative to a created time.

7. An apparatus for managing a cache in a distributed caching environment, the apparatus comprising:

means for receiving a cache notification event from a sending device, wherein the cache notification event includes time relative information and a clock value for the sending device;

means for determining a clock delta by determining a difference between the local clock and the clock value of the sending device; and

means for adjusting the time relative information in the cache notification event based upon the clock delta.

8. The apparatus of claim 7, further comprising:

means for validating the cache notification event.

9. The apparatus of claim 8, further comprising:

means for discarding the cache notification event if the cache notification event is invalid.

10. The apparatus of claim 7, wherein the cache notification event is one of an add event, an update event, and an invalidation event.

11. The apparatus of claim 7, wherein the time relative information is an expiration value.

12. The apparatus of claim 11, wherein the expiration value is one of a discrete time and an amount of time relative to a created time.

13. A cache component, in a server device, for managing a cache in a distributed caching environment, the cache component comprising:

a core cache that stores cache entries; and

a cache auditor that performs operations on entries in the core cache,

wherein the cache auditor receives a cache notification event from a sending device, wherein the cache notification event includes time relative information and a clock value for the sending device;

determines a clock delta by determining a difference between the local clock and the clock value of the sending device; and

adjusts the time relative information in the cache notification event based upon the clock delta.

14. The cache component of claim 13, wherein the cache auditor validates the cache notification event.

15. The cache component of claim 14, wherein the cache auditor discards the cache notification event if the cache notification event is invalid.

16. The cache component of claim 13, wherein the cache notification event is one of an add event, an update event, and an invalidation event.

17. The cache component of claim 13, wherein the time relative information is an expiration value.

18. The cache component of claim 17, wherein the expiration value is one of a discrete time and an amount of time relative to a created time.

19. A computer program product, in a computer readable medium, for managing a cache in a distributed caching environment, the computer program product comprising:

instructions for receiving a cache notification event from a sending device, wherein the cache notification event includes time relative information and a clock value for the sending device;

instructions for determining a clock delta by determining a difference between the local clock and the clock value of the sending device; and

instructions for adjusting the time relative information in the cache notification event based upon the clock delta.

20. The computer program product of claim 19, wherein the time relative information is an expiration value.