Locating potentially identical objects across multiple computers based on stochastic partitioning of workload

• US 20050097148A1
• Filed: 11/18/2004
• Published: 05/05/2005
• Est. Priority Date: 06/06/2001
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Theimer, Marvin M., Bolosky, William J., Douceur, John R., Adya, Atul
• Granted Patent: US 7,272,630 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 16/1748 De-duplication implemented within the file system, e.g. based on file segments de-duplication techniques in storage systems for the management of data blocks G06F3/0641
• CPC Class Codes: Y10S 707/99944 Object-oriented database structure
• CPC Class Codes: Y10S 707/99946 Object-oriented database structure network
• CPC Class Codes: Y10S 707/99952 Coherency, e.g. same view to multiple users
• CPC Class Codes: Y10S 707/99953 Recoverability

Abstract

Potentially identical objects (e.g., files) are located across multiple computers based on stochastic partitioning of workload. For each of a plurality of objects stored on a plurality of computers in a network, a portion of object information corresponding to the object is selected. The object information can be generated in a variety of manners (e.g., based on hashing the object, based on characteristics of the object, and so forth). Any of a variety of portions of the object information can be used (e.g., the least significant bits of the object information). A stochastic partitioning process is then used to identify which of the plurality of computers to communicate the object information to for identification of potentially identical objects on the plurality of computers.

Claims

1. A method comprising:

generating an imprint for an object stored at a computer, wherein the imprint comprises a first set of bits of object information corresponding to the object;

identifying one or more additional computers each having a computer identifier that includes a second set of bits that match the imprint; and

sending the object information to each of the identified one or more additional computers.

2. A method as recited in claim 1, wherein the object comprises a file and the object information comprises file information.

3. A method as recited in claim 1, wherein the first set of bits comprises the least significant bits of the object information, and wherein the second set of bits comprises the least significant bits of the computer identifier.

4. A method as recited in claim 1, wherein the object information is a semi-unique value based at least in part on the data in the object.

5. A method as recited in claim 1, wherein the communicating further comprises communicating an object identifier corresponding to the object along with the object information.

6. A method as recited in claim 1, further comprising storing the object information in an object information database stored at the computer.

7. A method as recited in claim 1, further comprising:

receiving object information corresponding to an object stored on another computer;

comparing the received object information to an object information database;

checking whether the received object information matches any of the object information in the database; and

determining that two potentially identical objects exist if the received object information matches any of the object information in the database.

8. A method as recited in claim 1, wherein the locations of the first set of bits correspond to the locations of the second set of bits.

9. A method as recited in claim 1, wherein the number of bits in the first set of bits is based at least in part on a count of computers that the computer is aware of in the network.

10. A method as recited in claim 1, wherein the number of bits in the first set of bits is based at least in part on an average number of computers that a particular object identifier should be communicated to.