Managing operations on stored data units

Patent metadata

Field	Value
Publication number	US-9875054-B2
Application number	US-201313787203-A
Country	US
Kind code	B2
Filing date	Mar 6, 2013
Priority date	Mar 6, 2013
Publication date	Jan 23, 2018
Grant date	Jan 23, 2018

Abstract

A system for managing storage of data units includes a data storage system configured to store multiple data blocks, at least some of the data blocks containing multiple data units, with at least a group of the data blocks being stored contiguously, thereby supporting a first read operation that retrieves data units from at least two adjacent data blocks in the group. The system is configured to perform one or more operations with respect to data units, the operations including a delete operation that replaces a first data block containing a data unit to be deleted with a second data block that does not contain the deleted data unit, with the second data block having the same size as the first data block.

First claim

What is claimed is:

1. A system for managing storage of data units, the system including:
a data storage system configured to store multiple data blocks, at least some of the data blocks containing multiple data units, with at least a group of the data blocks being stored contiguously, thereby supporting a first read operation that retrieves data units from at least two adjacent data blocks in the group; and
an interface, including at least one processor, coupled to the data storage system, and configured to perform one or more operations with respect to data units, the operations including a delete operation that replaces a first data block containing a data unit to be deleted with a second data block that does not contain the deleted data unit, and stores information about the deleted data unit and overhead information, both the information about the deleted data unit and the overhead information being stored within the second data block, and the size of the overhead information being dependent on the size of the information about the deleted data unit so that the second data block has the same size as the first data block after the information about the deleted data unit and the overhead information are stored within the second data block.

2. The system of claim 1 , wherein the second data block is adjacent to a data block that was adjacent to the first data block within the data storage system.

3. The system of claim 1 , wherein the second data block is stored in the same storage space as the first data block.

4. The system of claim 1 , wherein the delete operation maintains data blocks other than the first data block in the same storage locations within the data storage system in which they were stored before the delete operation was performed.

5. The system of claim 1 , wherein the data storage system is configured to store, for at least some of the data blocks, corresponding historical information about prior removal of one or more data units from that data block, the removal affecting at least some addresses of data units in that data block.

6. The system of claim 5 , wherein the operations include a second read operation, different from the first read operation, that accesses at least a first data unit stored in a particular data block according to address information interpreted based on any stored historical information corresponding to the particular data block.

7. The system of claim 5 , wherein the delete operation stores the information about the deleted data unit in historical information corresponding to the second data block.

8. The system of claim 5 , wherein at least some of the historical information is stored in the data storage system.

9. The system of claim 8 , wherein at least a portion of the historical information is interleaved between different data blocks.

10. The system of claim 8 , wherein at least a portion of historical information corresponding to a particular data block is stored in a predetermined portion of that particular data block.

11. The system of claim 1 , wherein at least some of the data blocks are compressed data blocks.

12. The system of claim 11 , wherein the second read operation decompresses a particular compressed data block to recover a set of decompressed data units and retrieves the data unit to be read at a particular offset from a reference location based at least in part on the historical information corresponding to that particular compressed data block.

13. The system of claim 11 , wherein the first read operation decompresses multiple compressed data blocks and reads multiple decompressed data units sequentially.

14. The system of claim 11 , wherein the first and second data blocks are compressed data blocks, and the delete operation expands a stored size of the second data block to account for a difference in size between the second data block and the first data block.

15. The system of claim 14 , wherein the stored size of the second data block is expanded by storing the overhead information within the second data block in addition to the historical information.

16. The system of claim 11 , wherein the delete operation stores a new error-detecting code associated with the second data block to replace an error-detecting code associated with the first data block.

17. The system of claim 11 , wherein the operations include an add operation that stores a data unit to be added in association with a set of recently added data units.

18. The system of claim 17 , wherein the processor is further configured to compress the set of recently added data units as a compressed data block stored in the storage medium.

19. The system of claim 1 , wherein the data storage system is configured to store overhead information identifying the data blocks in the group as conforming to a predetermined storage format.

20. The system of claim 19 , wherein the overhead information includes an identifier in a header of each data block in the group identifying the predetermined storage format.

21. The system of claim 19 , wherein the first read operation is compatible with the predetermined storage format.

22. A system for managing storage of data units, the system including:
means for storing multiple data blocks, at least some of the data blocks containing multiple data units, with at least a group of the data blocks being stored contiguously, thereby supporting a first read operation that retrieves data units from at least two adjacent data blocks in the group; and
means for performing one or more operations with respect to data units, the operations including a delete operation that replaces a first data block containing a data unit to be deleted with a second data block that does not contain the deleted data unit, and stores information about the deleted data unit and overhead information, both the information about the deleted data unit and the overhead information being stored within the second data block, and the size of the overhead information being dependent on the size of the information about the deleted data unit so that the second data block has the same size as the first data block after the information about the deleted data unit and the overhead information are stored within the second data block.

23. A method for managing storage of data units, the method including:
storing multiple data blocks in a data storage system, at least some of the data blocks containing multiple data units, with at least a group of the data blocks being stored contiguously, thereby supporting a first read operation that retrieves data units from at least two adjacent data blocks in the group; and
performing, using at least one processor, one or more operations with respect to data units, the operations including a delete operation that replaces a first data block containing a data unit to be deleted with a second data block that does not contain the deleted data unit, and stores information about the deleted data unit and overhead information, both the information about the deleted data unit and the overhead information being stored within the second data block, and the size of the overhead information being dependent on the size of the information about the deleted data unit so that the second data block has the same size as the first data block after the information about the deleted data unit and the overhead information are stored within the second data block.

24. Software stored on a computer-readable medium, for man

Assignees

• Ab Initio Technology Llc

Inventors

• Vishniac Ephraim Meriwether
• Schmidt Stephen J

Classifications

• G06F3/0608

  Saving storage space on storage systems · CPC title

• G06F3/064 Primary

  Management of blocks · CPC title

• G06F3/0671

  In-line storage system · CPC title