CACHE MANAGEMENT SYSTEM

• US 20100153652A1
• Filed: 12/09/2009
• Published: 06/17/2010
• 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 7,953,934 B2
• Time in Patent Office: Days
• US Class Current: 711/136
• 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 database storing a set of database assets;

a database server coupled to the database server;

a client computer coupled to the database server via a network and operable to retrieve database assets from the database server, the client computer comprising;

a processor;

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

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

wherein said cache manager is operable to store received database assets in the cache as cached digital assets and to poll said cached digital assets at different polling frequencies based upon indications of their activities,

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,

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.

2. The system of claim 1, wherein said first polling frequency is on the order of seconds.

3. The system of claim 2, wherein said second polling frequency is on the order of minutes.

4. The system of claim 1, wherein said first polling frequency is on the order of minutes.

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

6. A method comprising:

receiving at a client computer one or more database assets from a database server;

storing the one or more database assets as cached digital assets in a computer readable memory of the client computer;

polling cached digital assets at different frequencies, wherein each cached digital asset is polled with a frequency selected based on a level of activity associated with the cached digital asset; 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.

7. The method of claim 6, further comprising determining when a selected cached digital asset was last accessed or modified and determining whether to change the frequency of how often to poll the selected cached digital asset based on when the cached digital asset was last accessed or modified.

8. The method of claim 7, further comprising determining whether a second selected cached digital asset is to be automatically promoted to active status.

9. A system for managing a cache comprising:

a database server coupled to a database storing one or more database assets;

a client computer coupled to the database server by a network, the client computer operable to;

request a database asset from the database server;

store the database asset in a memory at the client computer as a cached asset;

assign the cached asset a first status;

poll the cached asset according to a first schedule corresponding to the first status and assign the cached asset a second status if the cached asset has not been active within a first period of time;

poll the cached asset according to a second schedule corresponding to the second status, wherein polling according to the first schedule occurs at a greater frequency than polling according to the second schedule.

10. The system of claim 9, wherein polling according to said first schedule and polling according to said second schedule further comprise processing a timestamp associated with said cached asset.

11. The system of claim 10, wherein said timestamp further comprises a last accessed timestamp.

12. The system of claim 10, wherein said timestamp further comprises a last modified timestamp.

13. The system of claim 9, wherein said client computer is further operable to poll the cached asset according to a third schedule corresponding to a third status.

14. The system of claim 13, wherein polling according to the third schedule occurs at a frequency that is less than polling according to the second schedule.

15. The system of claim 13, wherein the client computer is further operable to remove the cached asset from the cache if the cached asset has been not been active within a second period of time according to the polling according to the third schedule.