USING EXPLICIT DISK BLOCK CACHEABILITY ATTRIBUTES TO ENHANCE I/O CACHING EFFICIENCY

• US 20090070526A1
• Filed: 09/12/2007
• Published: 03/12/2009
• Est. Priority Date: 09/12/2007
• Status: Abandoned Application

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Tetrick, R. Scott, Juenemann, Dale J.
• Application Number:
  US11/854,376
• Publication Number:
  US 20090070526A1
• Time in Patent Office: Days
• US Class Current: 711/113
• CPC Class Codes: G06F 12/0866 for peripheral storage systems, e.g. disk cache
• CPC Class Codes: G06F 12/0888 using selective caching, e.g. bypass
• CPC Class Codes: G06F 2212/1021 Hit rate improvement

Abstract

A data caching method comprising identifying whether data stored in a first data block on a storage medium is cacheable; setting a first cacheability attribute associated with the first data block in a data structure to identify whether the data in the first data block is cacheable; monitoring I/O requests submitted for accessing target data in the first data block; determining whether the target data is cacheable based on the first cacheability attribute; and applying algorithms that implement cache policy to the target data, in response to determining that the target data is cacheable.

Claims

1. A data caching method comprising:

identifying whether data stored in a first data block on a storage medium is cacheable;

setting a first cacheability attribute associated with the first data block in a data structure to identify whether the data in the first data block is cacheable;

monitoring I/O requests submitted for accessing target data in the first data block;

determining whether the target data is cacheable based on the first cacheability attribute; and

applying algorithms that implement cache policy to the target data, in response to determining that the target data is cacheable.

2. The method of claim 1, further comprising circumventing cache to access target data, in response to determining that the target data is not cacheable.

3. The method of claim 1, wherein the data structure is an array comprising a plurality of bits, wherein each bit represents a first and a second value associated with a cacheability attribute for a data block on the storage medium.

4. The method of claim 1, wherein the storage medium is a rotatable storage medium.

5. The method of claim 3, wherein the first value represents that data stored in a corresponding data block is cacheable.

6. The method of claim 3, wherein the second value represents that data stored in a corresponding data block is not cacheable.

7. The method of claim 5, wherein the first value is approximately equal to “

1”

.

8. The method of claim 6, wherein the second value is approximately equal to “

0”

.

10. A data caching system comprising:

a logic unit for identifying whether data stored in a first data block on a storage medium is cacheable;

a logic unit for setting a first cacheability attribute associated with the first data block in a data structure to identify whether the data in the first data block is cacheable;

a logic unit for monitoring I/O requests submitted for accessing target data in the first data block;

a logic unit for determining whether the target data is cacheable based on the first cacheability attribute; and

a logic unit for applying algorithms that implement cache policy to the target data, in response to determining that the target data is cacheable.

11. The system of claim 10, further comprising a logic unit for failing to apply algorithms that implement cache policy to the target data, in response to determining that the target data is not cacheable.

12. The system of claim 10, wherein the data structure is an array comprising a plurality of bits, wherein each bit represents a first and a second value associated with a cacheability attribute for a data block on the storage medium.

13. The system of claim 10, wherein the storage medium is a rotatable storage medium.

14. The system of claim 12, wherein the first value represents that data stored in a corresponding data block is cacheable.

15. The system of claim 12, wherein the second value represents that data stored in a corresponding data block is not cacheable.