File generation for testing single-instance storage algorithm

• US 8,423,590 B2
• Filed: 05/30/2010
• Issued: 04/16/2013
• Est. Priority Date: 05/30/2010
• Status: Active Grant

• Current Assignee: Maplebear Inc.
• Original Assignee: International Business Machines Corporation
• Inventors: Nichols, Charles A.
• Primary Examiner(s): NGUYEN, MERILYN P
• Application Number:
  US12/790,845
• Publication Number:
  US 20110295916A1
• Time in Patent Office: 1,052 Days
• Field of Search: 707/822, 707/821
• US Class Current: 707/821
• CPC Class Codes: G06F 11/3684 for test design, e.g. generating new test cases
• CPC Class Codes: G06F 11/3688 for test execution, e.g. scheduling of test suites
• 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

Abstract

For each section of a buffer, a string of characters is retrieved and reordered to generate a reordered string of characters for the section. Thereafter, for each section of the buffer, the string of characters within the section is copied over with the reordered string of characters for a different section of the buffer. The buffer is then output to a file. If a desired length of the file has not yet been reached, then this process is repeated, or the buffer is again output to the file, based on a desired amount of duplicate data to be included within the file. The resulting file can be used to test a single-instance storage algorithm. The file is thus adapted to mimic a non-artificially generated file in relation to testing a single-instance storage algorithm.

Claims

1. A method comprising:

for each section of a plurality of sections of a buffer,

retrieving a string of characters from the section, by a computing device;

reordering characters within the string of characters, by the computing device, to generate a reordered string of characters for the section;

for each section of the plurality of sections of the buffer,

copying over the string of characters within the section with the reordered string of characters for a different section of the plurality of sections, by the computing device;

outputting the buffer to a file, the file adapted to mimic a non-artificially generated file in relation to testing a single-instance storage algorithm; and

,

testing the single-instance storage algorithm using the file by detecting a repeating pattern of data within the file, such that just one copy of the repeating pattern is stored within the file and other copies of the repeating pattern are each replaced within the file by a reference to the one copy of the repeating pattern stored within the file.

2. The method of claim 1, wherein the file is further adapted to mimic the non-artificially generated file in relation to testing a data compression algorithm, and wherein the method further comprises testing the data compression algorithm using the file.

3. The method of claim 1, wherein the file is a target file, and wherein the method further comprises filling the buffer from a source file.

4. The method of claim 1, further comprising dividing the buffer into the plurality of sections.

5. The method of claim 1, further comprising, after outputting the buffer to the file, and in response to determining that a desired length of the file has not yet been reached, performing one of repeating the method and outputting the buffer to the file again, based on a desired amount of duplicate data to be included within the file.

6. The method of claim 1, wherein the strings of characters retrieved from the sections and reordered are equal in length.

7. The method of claim 1, wherein a length of the string of characters retrieved from each section is less than a length of the section.

8. The method of claim 1, wherein reordering the characters within the string of characters comprises reversing an order of the characters within the string of characters.

9. The method of claim 1, further comprising, after reordering the characters within the string of characters to generate the reordered string of characters for the section,

copying the reordered string of characters to a current element of a ring buffer;

and,

rotating the ring buffer to change the current element of the ring buffer.

10. The method of claim 9, further comprising, before copying over the string of characters within the section with the reordered string of characters for a different section, rotating the ring buffer to change the current element of the ring buffer,

wherein copying over the string of characters within the section with the reordered string of characters for a different section comprises copying the reordered string of characters from the current element of the ring buffer.

11. The method of claim 1, wherein the reordered string of characters for each section is copied to just one other section of the buffer.

12. A method comprising:

for each section of a plurality of sections of a buffer,

retrieving a string of characters from the section, by a computing device;

reordering characters within the string of characters, by the computing device, to generate a reordered string of characters for the section;

for each section of the plurality of sections of the buffer,

copying over the string of characters within the section with the reordered string of characters for a different section of the plurality of sections, by the computing device;

outputting the buffer to a file, the file adapted to mimic a non-artificially generated file in relation to testing a single-instance storage algorithm;

testing the single-instance storage algorithm using the file;

determining an offset; and

,

incrementing the offset before each of one or more times the method is repeated,

wherein retrieving the string of characters from the section comprises retrieving the string of characters starting at a number of characters into the section equal to the offset.

13. A system comprising:

a processor;

a computer-readable data storage medium to store a file;

a memory including a buffer having a plurality of a plurality of sections;

a component implemented by the processor to generate the file by;

for each section of the buffer,

retrieving a string of characters from the section;

reordering characters within the string of characters to generate a reordered string of characters for the section;

for each section of the buffer,

copying over the string of characters within the section with the reordered string of characters for a different section of the buffer;

outputting the buffer to a file, the file adapted to mimic a non-artificially generated file in relation to testing a single-instance storage algorithm;

a testing component to test the single-instance storage algorithm by using the file,

wherein the component is further to generate the file by determining an offset, such that retrieving the string of characters from the section comprises retrieving the string of characters starting at a number of characters into the section equal to the offset.

14. The system of claim 13, wherein the testing component is to detect a repeating pattern of data within the file, such that just one copy of the repeating pattern is stored within the file and other copies of the repeating pattern are replaced by a reference to the one copy of the repeating pattern.

15. The system of claim 13, wherein the component is further to generate the file by:

after recording the characters within the string of characters to generate the reordered string of characters for the section,

copying the reordered string of characters to a current element of a ring buffer;

rotating the ring buffer to change the current element of the ring buffer,

before copying over the string of characters within the section with the reordered string of characters for a different section,

rotating the ring buffer to change the current element of the ring buffer,

wherein copying over the string of characters within the section with the reordered string of characters for a different section comprises copying the reordered string of characters from the current element of the ring buffer.

16. The system of claim 13, wherein the strings of characters retrieved from the sections and reordered are equal in length.

17. The system of claim 13, wherein a length of the string of characters retrieved from each section is less than a length of the section.