SELECTIVE COMPRESSION OF SYNCHRONIZED CONTENT BASED ON A CALCULATED COMPRESSION RATIO

• US 20080279462A1
• Filed: 05/10/2007
• Published: 11/13/2008
• Est. Priority Date: 05/10/2007
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: CELI, JOSEPH JR.
• Granted Patent: US 8,295,615 B2
• Time in Patent Office: Days
• US Class Current: 382/232
• CPC Class Codes: H04L 67/1095 Replication or mirroring of data, e.g. scheduling or transport for data synchronisation between network nodes
• CPC Class Codes: H04L 69/04 Protocols for data compression, e.g. ROHC

Abstract

The present invention discloses a system and method for synchronizing data between a first data store and a second data store. The system can include a synchronization component, a compression pre-processor, and a compression/decompression component. The synchronization component can automatically synchronize content between the first data store and the second data store. The compression pre-processor can determine a compression ratio for digital content before the digital content is compressed. The compression/decompression component can selectively compress digital content based upon the compression ratio determined by the compression pre-processor. The selectively compressed digital content can he automatically conveyed between the first data store and the second data store during synchronization operations involving the synchronization component. The compression/decompression component can automatically decompress received content that has been compressed. This decompression can occur automatically before adding the digital content to a content receiving data store.

Claims

1. A system for synchronizing data comprising:

a first data store and a second data store;

a synchronization component configured to automatically synchronize content between the first data store and the second data store;

a compression pre-processor configured to determine a compression ratio for digital content before the digital content is compressed; and

a compression/decompression component configured to selectively compress digital content based upon the compression ratio determined by the compression pre-processor, wherein the selectively compressed digital content is automatically conveyed between the first data store and the second data store during synchronization operations involving the synchronization component, and wherein the compression/decompression component automatically decompresses received content that has been compressed before adding the digital content to a receiving one of the first data store and the second data store.

2. The system of claim 1, wherein the first data store and the second data store are remotely located from each other.

3. The system of claim 1, wherein automatically synchronized content is conveyed between the first data store and the second data store within at least one hypertext transfer protocol (HTTP) based message.

4. The system of claim 1, wherein the HTTP based message conforms to a synchronization markup language that conforms to an open standard.

5. The system of claim 1, wherein the at least one HTTP based message includes selectively compressed digital content and a compression indicator that indicates whether the selectively compressed digital content has been compressed.

6. The system of claim 1, wherein the compression pre-processor and the compression/decompression component utilize a variant of a common compression algorithm, wherein the compression/decompression component utilizes a pattern dictionary during a compression pass that is generated by the pre-processor during a pre-processing pass.

7. A method for synchronizing data comprising:

initializing a synchronization action between two data stores;

determining digital content to be conveyed from one of the data stores to another;

executing a pre-processing compression algorithm to determine a compression ratio for the digital content when processed by a related compression algorithm;

when a set of programmatic actions determine that the compression ratio is sufficiently beneficial to merit compression, executing a compression algorithm to compress the digital content, conveying the digital content in the compressed format as part of the synchronization action form one data store to another, once conveyed automatically decompressing the digital content; and

when the set of programmatic actions determine that the compression ratio is not sufficiently beneficial to merit compression, conveying the uncompressed digital content as part of the synchronization action from one data store to another.

8. The method of claim 7, wherein the compression algorithm is a lossless compression algorithm, and wherein the set of programmatic actions specify that the determined compression ratio is sufficiently beneficial when a size of the compressed digital content as determined by the pre-processing compression algorithm is less than an uncompressed size of the digital content,

9. The method of claim 7, wherein conveyances of the digital content between the data stores uses at least one HTTP based message, wherein the HTTP based message comprises a compression indicator that indicates whether the digital content has been compressed and also comprises at least one of the compressed digital content and the uncompressed digital content.

10. The method of claim 7, wherein the pre-processing compression algorithm is a variant of the compression algorithm, wherein the pre-processing compression algorithm generates a pattern dictionary, which is used by the compression algorithm.

11. A method to selectively compress digital content comprising:

determining digital content to convey from one computing device to another;

executing a pre-processing compression pass to determine a compression ratio of the digital content when compressed;

comparing the compression ratio against at least one compression factor; and

selectively compressing the digital content based upon results of the comparing step.

12. The method of claim 11, wherein the compression factor includes a compression ratio threshold, wherein the compressing step is performed only when the determined compression ratio favorably compares to the compression ratio threshold, said method further comprising:

conveying the selectively compressed digital content from the one computing device to the another computing device.

13. The method of claim 11, wherein both the one computing device and the another computing device automatically perform the determining, executing, comparing, and selectively compressing steps in order to exchange digital content, wherein upon receiving exchanged digital content a receiving device selectively decompresses the selectively compressed digital content.

14. The method of claim 13, wherein the determining, executing, comparing, and selectively compressing steps, as well as a selectively decompressing step, are automatically performed by at least one of the one computing device and the another computing device in a fashion transparent to a device user.

15. The method of claim 11, further comprising:

conveying the selectively compressed digital content from the one computing device to the another computing device within a message conforming to a HTTP based protocol, wherein the conveyed message comprises a compression indicator of whether the digital content has been compressed;

the another computing device receiving the selectively compressed digital content;

the another computing device automatically determining whether the selectively compressed digital content has been compressed based upon a value of the compression indicator; and

the another computing device selectively decompressing the digital content based upon results of the automatically determining step.

16. The method of claim 11, wherein the determining, executing, comparing, and selectively compressing steps are used for synchronizing content, between a first data store associated with the one computing device and a second data store associated with the another computing device, wherein upon receiving exchanged digital content a receiving device automatically determines whether the digital content has been compressed and automatically decompresses compressed digital content.

17. The method of claim 16, wherein synchronizing content is programmatically performed in accordance with code stored upon a machine readable medium, said code being written in a synchronization markup language that conforms to an open standard.

18. The method of claim 16, wherein the selectively compressing step utilizes a modified variant of an algorithm used to compress the digital content in an event of a favorable comparison from the comparing step.

19. The method of claim 18, further comprising:

determining that the compression ratio favorably compares against the at least one compression factor;

generating a pattern dictionary during the pre-processing compression pass; and

performing a compression pass to compress the digital content, wherein the compression pass utilizes the generated pattern dictionary.

20. The method of claim 11, wherein said steps of claim 11 are steps performed automatically by at least one machine in accordance with at least one computer program having a plurality of code sections that are executable by the at least one machine, said at least one computer program being stored in a machine readable memory.