Data storage and caching architecture

• US 20040205092A1
• Filed: 03/27/2003
• Published: 10/14/2004
• Est. Priority Date: 03/27/2003
• Status: Active Grant

• Current Assignee: STMicroelectronics Incorporated (STMicroelectronics NV)
• Original Assignee: STMicroelectronics Incorporated (STMicroelectronics NV)
• Inventors: Lammers, Brett, Longo, Alan, Catalano, Glen, Wilson, Aaron Wade, Tempero, William Morgan, Lott, Glenn Alan
• Granted Patent: US 7,159,073 B2
• Time in Patent Office: Days
• US Class Current: 707/205
• CPC Class Codes: G06F 12/0871 Allocation or management of cache space
• CPC Class Codes: G06F 2212/312 In storage controller
• CPC Class Codes: G06F 2212/462 Track or segment
• CPC Class Codes: G06F 3/0613 in relation to throughput
• CPC Class Codes: G06F 3/064 Management of blocks
• CPC Class Codes: G06F 3/0656 Data buffering arrangements
• CPC Class Codes: G06F 3/0676 Magnetic disk device

Abstract

An extent record for an extent based data buffer that includes a host pointer that links the extent record to a next host extent record of a host extent record set, and a storage device pointer that links the extent record to a next storage device extent record of a storage device extent record set. Also, a system for transferring data between a host and a storage device that includes a data buffer coupled to the host and the storage device, where memory in the data buffer is divided into one or more extents, an extent table associated with the data buffer, where the extent table includes at least one extent record, an LBA chain table coupled to the host and the extent table, and a track section table coupled to the storage device and the extent table.

Claims

1. An extent record for an extent based data buffer comprising:

a host pointer that links the extent record to a next host extent record of a host extent record set; and

a storage device pointer that links the extent record to a next storage device extent record of a storage device extent record set.

2. The extent record of claim 1, wherein the host extent record set and the storage device extent record set comprise two or more extent records.

3. The extent record of claim 1, wherein the host extent record set defines locations of non-sequential extents in the data buffer.

4. The extent record of claim 3, wherein non-sequential extents comprise host LBA chain data from a host.

5. The extent record of claim 4, wherein said host device is a computer.

6. The extent record of claim 1, wherein the storage device extent record set defines locations for non-sequential extents in the data buffer.

7. The extent record of claim 6, wherein the non-sequential extents comprise track section data from a storage device.

8. The extent record of claim 7, wherein the storage device is a hard disk.

9. The extent record of claim 1, wherein the host extent set and the storage device extent record set share at least one extent record.

10. The extent record of claim 9, wherein the host extent record set has at least one extent record that is not in the storage device extent record set.

11. A system for transferring data between a host and a storage device comprising:

a data buffer coupled to the host and the storage device, wherein memory in the data buffer is divided into one or more extents;

an extent table associated with the data buffer, wherein the extent table comprises at least one extent record;

an LBA chain table coupled to the host and the extent table; and

a track section table coupled to the storage device and the extent table.

12. The system of claim 11 comprising a host pipe coupled to the host and the data buffer.

13. The system of claim 12, wherein the host pipe is coupled to the LBA chain table.

14. The system of claim 11 comprising a disk pipe coupled to the storage device and the data buffer.

15. The system of claim 14, wherein the disk pipe is coupled to the track section table.

16. The system of claim 11 comprising a buffer manager coupled to the data buffer.

17. The system of claim 16 comprising a hit detector coupled to the buffer manager, wherein the hit detector measures cache hits in the LBA chain table.

18. They system of claim 11, wherein the extent record comprises a host pointer and storage device pointer.

19. The system of claim 11, wherein the host is a computer.

20. The system of claim 11, wherein the storage device is a hard disk.

21. A method of searching an extent based data buffer comprising:

searching a host pointer in an extent record to find an LBA chain requested by a host; and

searching a storage device pointer in the extent record to find a track section requested by a storage device.

22. The method of claim 21, wherein said host pointer links the extent record to another host extent record in a host extent record set.

23. The method of claim 22, wherein the host extent record set defines the location of extents in the data buffer comprising data in a host LBA chain.

24. The method of claim 23, wherein said extents are non-sequential in the data buffer.

25. The method of claim 21, wherein said storage device pointer links the extent record to another storage device extent record in a storage device extent record set.

26. The method of claim 25, wherein the storage device extent record set defines the location of extents in the data buffer comprising data in a track section of a storage device.

27. The method of claim 26, wherein said extents are non-sequential in the data buffer.