SYSTEM, METHOD, AND COMPUTER PROGRAM PRODUCT FOR INSERTING A GAP IN INFORMATION SENT FROM A DRIVE TO A HOST DEVICE

• US 20110016233A1
• Filed: 07/17/2009
• Published: 01/20/2011
• Est. Priority Date: 07/17/2009
• Status: Active Grant

• Current Assignee: Seagate Technology LLC (Seagate Technology Holdings Plc)
• Original Assignee: LSI Corporation (Broadcom, Inc.)
• Inventors: Stenfort, Ross John
• Granted Patent: US 8,140,712 B2
• Time in Patent Office: Days
• US Class Current: 710/5
• CPC Class Codes: G06F 13/126 and has means for transferring I/O instructions and statuses between control unit and main processor
• CPC Class Codes: G06F 13/28 using burst mode transfer, e.g. direct memory access DMA, cycle steal G06F13/32 takes precedence
• CPC Class Codes: G06F 3/061 Improving I/O performance
• CPC Class Codes: G06F 3/0659 Command handling arrangements, e.g. command buffers, queues, command scheduling
• CPC Class Codes: G06F 3/0671 In-line storage system

Abstract

A system, method, and computer program product are provided for inserting a gap in information sent from a drive to a host device. In operation, one or more commands are received at a drive from a host device. Additionally, information is queued to send to the host device. Furthermore, a gap is inserted in the information to send to the host device such that the host device is capable of sending additional commands to the drive.

Claims

1. A method, comprising:

receiving one or more commands at a drive from a host device;

queuing information to send to the host device; and

inserting a gap in the information to send to the host device such that the host device is capable of sending additional commands to the drive.

2. The method of claim 1, wherein inserting the gap includes inserting a time delay.

3. The method of claim 2, wherein the information includes setup information and data associated with at least one of the one or more commands.

4. The method of claim 3, wherein the setup information includes a direct memory access (DMA) frame information structure (FIS).

5. The method of claim 3, wherein the setup information includes a set device bit FIS.

6. The method of claim 3, wherein the time delay is inserted before sending the setup information.

7. The method of claim 3, wherein the time delay is inserted after sending the setup information.

8. The method of claim 2, further comprising receiving the additional commands at the drive from the host device during a period of the time delay.

9. The method of claim 2, wherein inserting the time delay includes inserting the time delay during a period when the information is being sent to the host device.

10. The method of claim 9, wherein the time delay is inserted based on a current queue depth of the drive.

11. The method of claim 9, wherein the time delay is inserted based on an amount of time since a previous command was received.

12. The method of claim 9, wherein a length of time of the time delay is based on a current queue depth of the drive.

13. The method of claim 9, wherein a length of time of the time delay is based on an amount of time since a previous command was received by the drive.

14. The method of claim 2, wherein at least one of a length of time of tire time delay or a point when the time delay is inserted is determined in real time.

15. The method of claim 2, wherein at least one of a length of time of the time delay or a point when the time delay is inserted is a predetermined value.

16. The method of claim 2, wherein the information includes setup information including information indicating the time delay is following the setup information.

17. The method of claim 2, wherein the information includes status information and the time delay is inserted before sending the status information.

18. The method of claim 1, wherein inserting the gap includes inserting additional information.

19. The method of claim 1, wherein the host device is informed about the gap in advance of the gap.

20. The method of claim 1, wherein the drive includes a Serial ATA (SATA) drive.

21. A computer program product embodied on a computer readable medium, comprising:

computer code for receiving one or more commands at a drive from a host device;

computer code for queuing information to send to the host device; and

computer code for inserting a gap in the information to send to the host device such that the host device is capable of sending additional commands to the drive.

22. An apparatus, comprising:

a drive for receiving one or more commands from a host device;

a buffer for queuing information to send to the host device; and

a controller for inserting a gap in the information to send to the host device such that the host device is capable of sending additional commands to the drive.