Critical Resource Management

• US 20090193121A1
• Filed: 10/24/2008
• Published: 07/30/2009
• Est. Priority Date: 01/29/2008
• Status: Abandoned Application

• Current Assignee: George Shin
• Original Assignee: George Shin
• Inventors: Shin, George
• Application Number:
  US12/258,078
• Publication Number:
  US 20090193121A1
• Time in Patent Office: Days
• US Class Current: 709/225
• 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 3/0683 Plurality of storage devices
• CPC Class Codes: G06F 9/5011 the resources being hardware resources other than CPUs, Servers and Terminals
• CPC Class Codes: H04L 49/90 Buffering arrangements

Abstract

In one embodiment, a method of managing critical resource usage in a storage network comprises receiving, in a storage controller, an input/output operation from a host, wherein the input/output operation identifies a storage unit, placing the input/output operation in a waiting queue, determining a maximum queue depth for at least one critical resource in the storage network required to execute the input/output command against the storage unit, and blocking one or more subsequent input/output commands from the host for the storage unit when the wait queue for the critical resource exceeds the maximum queue depth.

Claims

1. A method of managing critical resource usage in a storage network comprising:

receiving, in a storage controller, an input/output operation from a host, wherein the input/output operation identifies a storage unit;

placing the input/output operation in a waiting queue;

determining a maximum queue depth for at least one critical resource in the storage network required to execute the input/output command against the storage unit; and

blocking one or more subsequent input/output commands from the host for the storage unit when the wait queue for the critical resource exceeds the maximum queue depth.

2. The method of claim 1, wherein determining a maximum queue depth for at least one critical resource in the storage network comprises dividing a number of available resources by a number of initiators waiting for the resources.

3. The method of claim 1 wherein blocking subsequent input/output commands from the host for the storage unit when the wait queue for the critical resource exceeds the maximum queue depth comprises transmitting to the host a message indicating that the input/output command has been blocked.

4. The method of claim 1, further comprising transmitting the maximum queue depth to a peer storage controller.

5. The method of claim 4, further comprising:

receiving, in the peer storage controller, an input/output operation that from the host that identifies the storage unit; and

processing the input/output operation using the maximum queue depth.

6. The method of claim 1, further comprising:

detecting a drop in usage of the critical resource; and

enabling one or more input/operations on the wait queue.

7. The method of claim 6, further comprising:

enabling one or more subsequent input/output operations.

8. A storage controller, comprising:

a processor;

a memory module comprising logic instructions stored in a computer-readable medium which, when executed by the processor, configure the controller to;

receive, in the storage controller, an input/output operation from a host, wherein the input/output operation identifies a storage unit;

place the input/output operation in a waiting queue;

determine a maximum queue depth for at least one critical resource in a storage network required to execute the input/output command against the storage unit; and

block one or more subsequent input/output commands from the host for the storage unit when the wait queue for the critical resource exceeds the maximum queue depth.

9. The storage controller of claim 8, further comprising logic instructions stored on a computer-readable medium which, when executed, configure the controller to determine a maximum queue depth for at least one critical resource in the storage network by dividing a number of available resources by a number of initiators waiting for the resources.

10. The storage controller of claim 8, further comprising logic instructions stored on a computer-readable medium which, when executed, configure the controller to transmit to the host a message indicating that the input/output command has been blocked.

11. The storage controller of claim 8, further comprising logic instructions stored on a computer-readable medium which, when executed, configure the controller to transmit the maximum queue depth to a peer storage controller.

12. The storage controller of claim 8, further comprising logic instructions stored on a computer-readable medium which, when executed, configure the controller to:

receive, in the peer storage controller, an input/output operation that from the host that identifies the storage unit; and

process the input/output operation using the maximum queue depth.

13. The storage controller of claim 8, further comprising logic instructions stored on a computer-readable medium which, when executed, configure the controller to:

detect a drop in usage of the critical resource; and

enable one or more input/operations on the wait queue.

14. The storage controller of claim 13, further comprising logic instructions stored on a computer-readable medium which, when executed, configure the controller to:

enable one or more subsequent input/output operations.

15. A computer program product comprising logic instructions stored in a computer-readable medium which, when executed by a processor in a storage controller, configure the controller to:

receive, in the storage controller, an input/output operation from a host, wherein the input/output operation identifies a storage unit;

place the input/output operation in a waiting queue;

determine a maximum queue depth for at least one critical resource in a storage network required to execute the input/output command against the storage unit; and

block one or more subsequent input/output commands from the host for the storage unit when the wait queue for the critical resource exceeds the maximum queue depth.

16. The computer program product of claim 15, further comprising logic instructions stored on a computer-readable medium which, when executed, configure the controller to determine a maximum queue depth for at least one critical resource in the storage network by dividing a number of available resources by a number of initiators waiting for the resources.

17. The computer program product of claim 15, further comprising logic instructions stored on a computer-readable medium which, when executed, configure the controller to transmit to the host a message indicating that the input/output command has been blocked.

18. The computer program product of claim 15, further comprising logic instructions stored on a computer-readable medium which, when executed, configure the controller to transmit the maximum queue depth to a peer storage controller.

19. The computer program product of claim 15, further comprising logic instructions stored on a computer-readable medium which, when executed, configure the controller to:

receive, in the peer storage controller, an input/output operation that from the host that identifies the storage unit; and

process the input/output operation using the maximum queue depth.

20. The computer program product of claim 15, further comprising logic instructions stored on a computer-readable medium which, when executed, configure the controller to:

detect a drop in usage of the critical resource; and

enable one or more input/operations on the wait queue.