FILE BUNDLING FOR CACHE SERVERS OF CONTENT DELIVERY NETWORKS

• US 20110276623A1
• Filed: 05/06/2010
• Published: 11/10/2011
• Est. Priority Date: 05/06/2010
• Status: Active Grant

• Current Assignee: Cdnetworks Holdings Singapore Pte., Ltd. (Wangsu Science & Technology Co., Ltd.)
• Original Assignee: Cdnetworks Company Limited (Wangsu Science & Technology Co., Ltd.)
• Inventors: Girbal, Antoine Jean
• Granted Patent: US 8,463,846 B2
• Time in Patent Office: Days
• US Class Current: 709/203
• CPC Class Codes: G06F 16/172 Caching, prefetching or hoarding of files

Abstract

Data access time in content delivery networks is improved by storing files in cache servers as file bundles. A cache server determines that multiple files are requested by the same client based on information available in the request including the IP address of the client, a URL of a webpage referring to the file, and/or a cookie stored at a client. The cache server stores multiple files requested by the same client on the hard drive as a file bundle with meta data associating the files with one another, such that they can be accessed together. A future request from the client for a file in a file bundle results in multiple files from the file bundle being loaded in the memory. If the client requests another file from the file bundle, the file is accessed directly from the memory instead of the hard drive, resulting in improved performance.

Claims

1. In a cache server of a content delivery network including a plurality of cache servers, a computer-implemented method for storing files on the cache server, the method comprising:

receiving a first request for a first file;

retrieving the first file from a first content source;

receiving a second request for a second file;

retrieving the second file from the first content source or a second content source; and

responsive to determining that the first request and the second request are received from a same client, storing the first file and the second file on a storage device of the cache server with metadata associating the first file with the second file in a file bundle.

2. The method of claim 1, wherein determining that the first request and the second request are received from a same client comprises:

identifying a first parameter associated with the first request, wherein the first parameter is associated with the first client;

identifying a second parameter associated with the second request, wherein the second parameter is associated with the second client; and

determining that the first parameter matches the second parameter.

3. The method of claim 1, wherein the first request and the second request are determined to be from a same client if the first request and the second request are received from a same connection between the client and the cache server.

4. The method of claim 1, wherein the first request and the second request are determined to be from a same client if a first network address obtained from the first request is identical to a second network address obtained from the second request.

5. The method of claim 1, wherein the first request and the second request are determined to be from a same client if a first cookie obtained from the first request matches a second cookie obtained from the second request.

6. The method of claim 1, wherein the first file and second file are stored on the storage device in adjacent locations.

7. The method of claim 1, wherein the cache server is a first cache server of an edge point of presence (POP) of the content delivery network and the first content source is a second cache server of the edge POP of the content delivery network.

8. The method of claim 1, wherein the cache server is in a first edge point of presence (POP) of the content delivery network and the first content source is another cache server in a second edge POP of the content delivery network.

9. The method of claim 1, wherein the first content source is an origin server.

10. The method of claim 1, wherein the metadata comprises a pointer from the first file to the second file in the storage device.

11. The method of claim 1, wherein the first file and the second file are stored on the storage device in the file bundle such that the first and the second file can be read by a single seek operation of the storage device.

12. The method of claim 1, further comprising:

receiving a third request for a third file;

retrieving the third file from a third content source; and

responsive to determining that the third request is received from another client different from the client from which the first request and the second request are received, storing the third file on the storage device of the cache server in another file bundle different from said file bundle in which the first file and the second file are stored.

13. The method of claim 1, wherein the first file and the second file of the file bundle are temporarily stored in a memory device of the cache server before the first file and the second file are stored in the storage device.

14. The method of claim 13, wherein the first file and the second file are stored in the storage device after a predetermined amount of time passes since storage of the first file and the second file in the memory device of the cache server.

15. The method of claim 13, wherein the first file and the second file are stored in the storage device after a predetermined number of files are included in the file bundle that is temporarily stored in the memory device.

16. In a first cache server of a content delivery network including a plurality of cache servers, a computer-implemented method for retrieving content, the method comprising:

receiving from a client at the first cache server a request for a first file;

determining whether the first file belongs to a file bundle, the file bundle including a plurality of files including at least a first file and a second file and metadata associating the first file with the second file and stored in a storage device of the first cache server;

responsive to determining that the first file belongs to the file bundle, retrieving at least the first file and the second file from the storage device into a memory of the cache server; and

sending the retrieved first file to the client.

17. The method of claim 16, further comprising:

receiving at the first cache server from the client a request for the second file;

responsive to determining that the second file belongs to the file bundle, accessing the second file previously retrieved into the memory of the first cache server with the first file; and

sending the second file to the client.

18. The method of claim 16, further comprising:

responsive to determining that the first cache server is not the owner of the first file, requesting the first file from a second cache server of the content delivery network;

receiving at least the first file and information indicating that the second file is stored in the file bundle stored in another storage device of the second cache server;

updating a file affinity table including said information that the second file is stored in said another storage device of the second cache server.

19. The method of claim 18, further comprising receiving at the first cache server from the client a request for the second file;

determining that second request is from the same client as the first request and that the second file belongs to the file bundle;

determining that the second file is stored in said another storage device of the second cache server based on said information in the file affinity table;

receiving the second file from the second cache server; and

sending the second file to the client.

20. In a first cache server of a content delivery network including a plurality of cache servers, a computer-implemented method for delivering content, the method comprising:

receiving from a second cache server a request for a first file;

retrieving the first file and a second file stored in a file bundle on a storage device of the first cache server, wherein the first file and the second file were previously requested by a same client and are stored on the storage device with metadata associating the first file with the second file; and

sending the first file and information indicative of the second file to the second cache server.

21. The method of claim 20, further comprising

receiving at the first cache server from the second cache server a request for the second file;

accessing the second file previously retrieved into the memory of the first cache server; and

sending the second file to the second cache server.

22. A cache server of a content delivery network including at least a processor and a computer readable storage medium storing computer instructions configured to cause the processor to perform a computer-implemented method of storing files on the cache server, the method comprising:

receiving a first request for a first file;

retrieving the first file from a first content source;

receiving a second request for a second file;

retrieving the second file from the first content source or a second content source; and

responsive to determining that the first request and the second request are received from a same client, storing the first file and the second file on a storage device of the cache server with metadata associating the first file with the second file in a file bundle.

23. The cache server of claim 22, wherein determining that the first request and the second request are received from a same client comprises:

identifying a first parameter associated with the first request, wherein the first parameter is associated with the first client;

identifying a second parameter associated with the second request, wherein the second parameter is associated with the second client; and

determining that the first parameter matches the second parameter.

24. The cache server of claim 22, wherein the method further comprises

receiving a third request for a third file;

retrieving the third file from a third content source; and

responsive to determining that the third request is received from another client different from the client from which the first request and the second request are received, storing the third file on the storage device of the cache server in another file bundle different from said file bundle in which the first file and the second file are stored.

25. A computer readable storage medium storing a computer program product including computer instructions configured to cause a processor of a computer to perform a computer-implemented method of storing files on a cache server of a content delivery network, the method comprising:

receiving a first request for a first file;

retrieving the first file from a first content source;

receiving a second request for a second file;

retrieving the second file from the first content source or a second content source; and

responsive to determining that the first request and the second request are received from a same client, storing the first file and the second file on a storage device of the cache server with metadata associating the first file with the second file in a file bundle.

26. The computer readable storage medium of claim 25, wherein determining that the first request and the second request are received from a same client comprises:

identifying a first parameter associated with the first request, wherein the first parameter is associated with the first client;

identifying a second parameter associated with the second request, wherein the second parameter is associated with the second client; and

determining that the first parameter matches the second parameter.

27. The computer readable storage medium of claim 25, wherein the method further comprises

receiving a third request for a third file from the content delivery network;

retrieving the third file from a third content source; and

responsive to determining that the third request is received from another client different from the client from which the first request and the second request are received, storing the third file on the storage device of the cache server in another file bundle different from said file bundle in which the first file and the second file are stored.