MODIFYING A COMPRESSED BLOCK OF DATA

• US 20170060934A1
• Filed: 09/02/2015
• Published: 03/02/2017
• Est. Priority Date: 09/02/2015
• Status: Active Application

• Current Assignee: Pure Storage, Inc.
• Original Assignee: Pure Storage, Inc.
• Inventors: SAPUNTZAKIS, CONSTANTINE
• Application Number:
  US14/842,947
• Publication Number:
  US 20170060934A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 16/2291 User-Defined Types; Storage management thereof
• CPC Class Codes: G06F 16/2365 Ensuring data consistency and integrity
• CPC Class Codes: G06F 3/0608 Saving storage space on storage systems
• CPC Class Codes: G06F 3/064 Management of blocks
• CPC Class Codes: G06F 3/0673 Single storage device

Abstract

Modifying a compressed block of data, including: splitting the compressed block of data into a leading compressed portion and a trailing compressed portion, wherein neither the leading compressed portion nor the trailing compressed portion includes an outdated portion of the compressed block of data; creating an updated compressed block to replace the outdated portion; and combining the leading compressed portion, the updated compressed block, and the trailing compressed portion.

Claims

1. A method of modifying a compressed block of data, the method comprising:

splitting the compressed block of data into a leading compressed portion and a trailing compressed portion, wherein neither the leading compressed portion nor the trailing compressed portion includes an outdated portion of the compressed block of data;

creating an updated compressed block to replace the outdated portion; and

combining the leading compressed portion, the updated compressed block, and the trailing compressed portion.

2. The method of claim 1 wherein splitting the compressed block of data into the leading compressed portion and the trailing compressed portion further comprises:

performing a truncation operation on the compressed block of data; and

performing an offset truncation operation on the compressed block of data.

3. The method of claim 1 wherein splitting the compressed block of data into the leading compressed portion and the trailing compressed portion further comprises removing references to the outdated portion from the trailing compressed portion.

4. The method of claim 1 wherein combining the leading compressed portion, the updated compressed block, and the trailing compressed portion further comprises combining the leading compressed portion, the updated compressed block, and the trailing compressed portion without recompressing any of the portions.

5. The method of claim 1 wherein combining the leading compressed portion, the updated compressed block, and the trailing compressed portion further comprises performing a partial recompression of the leading compressed portion, the updated compressed block, and the trailing compressed portion.

6. The method of claim 1 wherein combining the leading compressed portion, the updated compressed block, and the trailing compressed portion further comprises:

inserting a flush token between the leading compressed portion and the updated compressed block; and

inserting a flush token between the updated compressed block and the trailing compressed portion.

7. The method of claim 1 wherein combining the leading compressed portion, the updated compressed block, and the trailing compressed portion further comprises updating a first literal in the updated compressed block to be a mid-block literal.

8. An apparatus for modifying a compressed block of data, the apparatus including a computer processor and a computer memory, the computer memory including computer program instructions that, when executed by the computer processor, cause the apparatus to carry out the steps of:

splitting the compressed block of data into a leading compressed portion and a trailing compressed portion, wherein neither the leading compressed portion nor the trailing compressed portion includes an outdated portion of the compressed block of data;

creating an updated compressed block to replace the outdated portion; and

combining the leading compressed portion, the updated compressed block, and the trailing compressed portion.

9. The apparatus of claim 8 wherein splitting the compressed block of data into the leading compressed portion and the trailing compressed portion further comprises:

performing a truncation operation on the compressed block of data; and

performing an offset truncation operation on the compressed block of data.

10. The apparatus of claim 8 wherein splitting the compressed block of data into the leading compressed portion and the trailing compressed portion further comprises removing references to the outdated portion from the trailing compressed portion.

11. The apparatus of claim 8 wherein combining the leading compressed portion, the updated compressed block, and the trailing compressed portion further comprises combining the leading compressed portion, the updated compressed block, and the trailing compressed portion without recompressing any of the portions.

12. The apparatus of claim 8 wherein combining the leading compressed portion, the updated compressed block, and the trailing compressed portion further comprises performing a partial recompression of the leading compressed portion, the updated compressed block, and the trailing compressed portion.

13. The apparatus of claim 8 wherein combining the leading compressed portion, the updated compressed block, and the trailing compressed portion further comprises:

inserting a flush token between the leading compressed portion and the updated compressed block; and

inserting a flush token between the updated compressed block and the trailing compressed portion.

14. The apparatus of claim 8 wherein combining the leading compressed portion, the updated compressed block, and the trailing compressed portion further comprises updating a first literal in the updated compressed block to be a mid-block literal.

15. A computer program product for modifying a compressed block of data, the computer program product disposed upon a computer readable medium, the computer program product comprising computer program instructions that, when executed, cause a computer to carry out the steps of:

splitting the compressed block of data into a leading compressed portion and a trailing compressed portion, wherein neither the leading compressed portion nor the trailing compressed portion includes an outdated portion of the compressed block of data;

creating an updated compressed block to replace the outdated portion; and

combining the leading compressed portion, the updated compressed block, and the trailing compressed portion.

16. The computer program product of claim 15 wherein splitting the compressed block of data into the leading compressed portion and the trailing compressed portion further comprises:

performing a truncation operation on the compressed block of data; and

performing an offset truncation operation on the compressed block of data.

17. The computer program product of claim 15 wherein splitting the compressed block of data into the leading compressed portion and the trailing compressed portion further comprises removing references to the outdated portion from the trailing compressed portion.

18. The computer program product of claim 15 wherein combining the leading compressed portion, the updated compressed block, and the trailing compressed portion further comprises combining the leading compressed portion, the updated compressed block, and the trailing compressed portion without recompressing any of the portions.

19. The computer program product of claim 15 wherein combining the leading compressed portion, the updated compressed block, and the trailing compressed portion further comprises performing a partial recompression of the leading compressed portion, the updated compressed block, and the trailing compressed portion.

20. The computer program product of claim 15 wherein combining the leading compressed portion, the updated compressed block, and the trailing compressed portion further comprises:

inserting a flush token between the leading compressed portion and the updated compressed block; and

inserting a flush token between the updated compressed block and the trailing compressed portion.