CACHE MANAGEMENT SYSTEM WITH APPLICATION-INDEPENDENT POLLING

• US 20080034133A1
• Filed: 10/12/2007
• Published: 02/07/2008
• Est. Priority Date: 12/28/2001
• Status: Active Grant

• Current Assignee: Ip Ot Sub Ulc
• Original Assignee: Vignette Corporation (Open Text Corporation)
• Inventors: Thomas, David, Wells, Scott
• Granted Patent: US 7,647,453 B2
• Time in Patent Office: Days
• US Class Current: 710/44
• CPC Class Codes: G06F 12/0866 for peripheral storage systems, e.g. disk cache
• CPC Class Codes: G06F 12/123 with age lists, e.g. queue, most recently used [MRU] list or least recently used [LRU] list
• CPC Class Codes: G06F 16/9574 of access to content, e.g. by caching
• CPC Class Codes: G06F 2212/264 Remote server
• CPC Class Codes: G06F 2212/465 Structured object, e.g. database record
• CPC Class Codes: H04L 67/568 Storing data temporarily at an intermediate stage, e.g. caching

Abstract

Embodiments disclosed herein provide a cache management system comprising a cache and a cache manager that can poll cached assets at different frequencies based on their relative activity status and independent of other applications. In one embodiment, the cache manager may maintain one or more lists, each corresponding to a polling layer associated with a particular polling schedule or frequency. Cached assets may be added to or removed from a list or they may be promoted or demoted to a different list, thereby changing their polling frequency. By polling less active files at a lower frequency than more active files, significant system resources can be saved, thereby increasing overall system speed and performance. Additionally, because a cache manager according to embodiments disclosed herein does not require detailed contextual information about the files that it is managing, such a cache manager can be easily implemented with any cache.

Claims

1. A system comprising:

a processor;

a computer readable memory coupled to said processor and storing a cache manager, said a computer readable memory comprising;

a cache maintained by said cache manager and containing cached digital assets, wherein said cache manager is operable to poll said cached digital assets at different polling frequencies based upon indications of their activities.

2. The system of claim 1, wherein said computer readable memory further comprises one or more file lists maintained by said cache manager and containing entries associated with said cached digital assets, wherein said one or more file lists correspond to polling of said cached digital assets at said different polling frequencies.

3. The system of claim 2, wherein said cache manager is operable to determine when a cached digital asset was last accessed or modified and determine whether an entry associated with said cached digital asset is to be removed from or add to a file list.

4. The system of claim 2, wherein said cache manager is operable to determine when a cached digital asset was last accessed or modified and determine whether an entry associated with said cached digital asset is to be promoted to a first file list corresponding to a first polling frequency or demoted to a second file list corresponding to a second polling frequency, wherein said first polling frequency is higher than said second polling frequency.

5. The system of claim 4, wherein said first polling frequency is on the order of seconds.

6. The system of claim 5, wherein said second polling frequency is on the order of minutes.

7. The system of claim 4, wherein said first polling frequency is on the order of minutes.

8. The system of claim 7, wherein said second polling frequency is on the order of hours.

9. The system of claim 2, wherein said cache manager is operable to read at least one time stamp associated with a cached digital asset and determine whether to remove said cached digital asset from said cache or demote an entry associated with said cached digital asset to a non-active file list.

10. The system of claim 2, wherein said cache manager is operable to determine whether to remove a cached digital asset from said cache based on whether number of non-active cached digital assets has exceeded a certain size or whether said cached digital asset has not been active within a predetermined period of time.

11. The system of claim 2, wherein said cache manager is operable to monitor said cached digital assets and determine whether a cached digital asset is to be automatically promoted to active status.

12. A computer readable memory storing a cache manager, said a computer readable memory comprising:

a cache maintained by said cache manager and containing cached digital assets; and

one or more file lists maintained by said cache manager and containing entries associated with said cached digital assets, wherein said one or more file lists correspond to polling of said cached digital assets at different frequencies and wherein said cache manager is operable to poll said cached digital assets at said different frequencies and change or maintain status of said cached digital assets accordingly.

13. The computer readable memory of claim 12, wherein said cache manager is operable to determine when a cached digital asset was last accessed or modified and determine whether an entry associated with said cached digital asset is to be removed from or add to a file list.

14. The computer readable memory of claim 12, wherein said cache manager is operable to determine when a cached digital asset was last accessed or modified and determine whether an entry associated with said cached digital asset is to be promoted to a first file list corresponding to a first polling frequency or demoted to a second file list corresponding to a second polling frequency, wherein said first polling frequency is higher than said second polling frequency.

15. The computer readable memory of claim 12, wherein said cache manager is operable to read at least one time stamp associated with a cached digital asset and determine whether to remove said cached digital asset from said cache or demote an entry associated with said cached digital asset to a non-active file list.

16. The computer readable memory of claim 12, wherein said cache manager is operable to determine whether to remove a cached digital asset from said cache based on whether number of non-active cached digital assets has exceeded a certain size or whether said cached digital asset has not been active within a predetermined period of time.

17. The computer readable memory of claim 12, wherein said cache manager is operable to monitor said cached digital assets and determine whether a cached digital asset is to be automatically promoted to active status.

18. A method comprising:

creating and maintaining a plurality of polling layers in a computer readable memory, wherein said computer readable memory stores a cache manager and comprises a cache maintained by said cache manager;

polling cached digital assets at different frequencies corresponding to said plurality of polling layers; and

after polling a cached digital asset, changing or maintaining status of said cached digital asset accordingly, wherein changing said status of said cached digital asset moves said cached digital asset between a first polling layer and a second polling layer, wherein said first polling layer corresponds to a first polling frequency, wherein said second polling layer corresponds to a second polling frequency, and wherein said first polling frequency is higher than said second polling frequency.

19. The method of claim 18, further comprising determining when said cached digital asset was last accessed or modified and determining whether said cached digital asset is to be promoted to said first polling layer or demoted to said second polling layer.

20. The method of claim 18, further comprising determining whether a second cached digital asset is to be automatically promoted to active status.