SYSTEMS AND METHODS FOR BYTE-LEVEL OR QUASI BYTE-LEVEL SINGLE INSTANCING

• US 20100169287A1
• Filed: 11/27/2009
• Published: 07/01/2010
• Est. Priority Date: 11/26/2008
• Status: Active Grant

• Current Assignee: CommVault Systems Incorporated
• Original Assignee: CommVault Systems Incorporated
• Inventors: Klose, Michael F.
• Granted Patent: US 8,412,677 B2
• Time in Patent Office: Days
• US Class Current: 707/692
• CPC Class Codes: G06F 11/1453 using de-duplication of the data
• CPC Class Codes: G06F 16/113 Details of archiving lifecycle management in storage systems G06F3/0649; backup systems G06F11/1446
• CPC Class Codes: G06F 16/13 File access structures, e.g. distributed indices arrangements of input from, or output to, record carriers G06F3/06
• 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: G06F 16/1752 based on file chunks
• CPC Class Codes: G06F 16/18 File system types
• CPC Class Codes: G06F 16/184 implemented as replicated file system
• CPC Class Codes: G06F 16/185 Hierarchical storage management [HSM] systems, e.g. file migration or policies thereof details of archiving G06F16/11

Abstract

Described in detail herein are systems and methods for deduplicating data using byte-level or quasi byte-level techniques. In some embodiments, a file is divided into multiple blocks. A block includes multiple bytes. Multiple rolling hashes of the file are generated. For each byte in the file, a searchable data structure is accessed to determine if the data structure already includes an entry matching a hash of a minimum sequence length. If so, this indicates that the corresponding bytes are already stored. If one or more bytes in the file are already stored, then the one or more bytes in the file are replaced with a reference to the already stored bytes. The systems and methods described herein may be used for file systems, databases, storing backup data, or any other use case where it may be useful to reduce the amount of data being stored.

Claims

1. A method of deduplicating data, wherein the method is performed by a computing system having a processor and memory, the method comprising:

storing multiple blocks of data in a data structure, wherein;

the multiple blocks of data have an first size,

the multiple blocks of data represent a set of data having a second size that is greater than the first size,

a block of data is associated with multiple first identifiers, and

the multiple blocks of data are sorted in the data structure by the associated multiple first identifiers;

receiving a file, the file including multiple bytes;

accessing the data structure;

based at least partly upon accessing the data structure, determining, by the computing system, whether one or more of the multiple bytes are already stored, wherein the number of the one or more bytes is less than a number of bytes in a block of data; and

storing bytes that are not already stored using a storage device.

2. The method of claim 1, further comprising generating multiple second identifiers for the file, wherein the multiple second identifiers for the file include powers of 2 rolling hashes.

3. The method of claim 1, further comprising generating multiple second identifiers for the file, wherein the multiple second identifiers include powers of 2 rolling hashes, and wherein determining whether the one or more of the multiple bytes are already stored includes comparing the multiple second identifiers for the file with the multiple first identifiers associated with the multiple blocks of data.

4. The method of claim 1 wherein the data structure includes a hierarchical data structure that includes multiple nodes, and wherein a first node can reference data in any other node excepting nodes that are descendants of the first node.

5. The method of claim 1 wherein multiple blocks of data are compressed.

6. A computing system for deduplicating data, the computing system comprising:

a processor;

a memory;

means for receiving a first set of data;

means for dividing the first set of data into at least one block, the block including a total number of bytes;

means for accessing a searchable data structure, the searchable data structure including a second set of data;

means for determining whether one or more bytes of the block are included in a portion of the second set of data in the searchable data structure, wherein the number of the one or more bytes is less than the total number of bytes of the block;

means for replacing the one or more bytes with a reference to the portion of the second set of data, wherein the means for replacing replaces the one or more bytes with a reference to the portion of the second set of data if the one or more bytes of the block are included in the portion of the second set of data in the searchable data structure; and

means for storing the block.

7. The computing system of claim 6, further comprising means for generating powers of 2 rolling hashes.

8. The computing system of claim 6 wherein the searchable data structure includes a hierarchical data structure that includes multiple nodes, and wherein a first node can reference data in any other node excepting nodes that are descendants of the first node.

9. The computing system of claim 6, further comprising means for compressing data.

10. A system for deduplicating data in a data storage network, wherein the data storage network includes one or more storage devices coupled via a network, and wherein the network also couples to one or more computing systems, the system comprising:

one or more storage devices storing a searchable data structure, the searchable data structure including a first set of data; and

a computing system configured to;

receive a second set of data;

divide the set of data into at least one block, the block including a total number of bytes;

access the searchable data structure;

determine whether one or more bytes of the block are included in a portion of the first set of data in the searchable data structure, wherein the number of the one or more bytes is less than the total number of bytes of the block;

replace the one or more bytes with a reference to the portion of the second set of data if the one or more bytes of the block are included in the portion of the first set of data in the searchable data structure; and

store the block using the one or more storage devices.

11. The system of claim 10 wherein the computing system is further configured to generate powers of 2 rolling hashes for the second set of data.

12. The system of claim 10 wherein the searchable data structure includes a hierarchical data structure that includes multiple nodes, and wherein a first node can reference data in any other node excepting nodes that are descendants of the first node.

13. The system of claim 10 wherein the computing system is further configured to compress the second set of data.