SYSTEM AND PROGRAM PRODUCTS FOR FACILITATING INPUT/OUTPUT PROCESSING BY USING TRANSPORT CONTROL WORDS TO REDUCE INPUT/OUTPUT COMMUNICATIONS

• US 20110060848A1
• Filed: 11/15/2010
• Published: 03/10/2011
• Est. Priority Date: 10/10/2006
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Flanagan, John R., Casper, Daniel F.
• Granted Patent: US 8,140,713 B2
• Time in Patent Office: Days
• US Class Current: 710/11
• CPC Class Codes: G06F 13/126 and has means for transferring I/O instructions and statuses between control unit and main processor

Abstract

A computer program product, apparatus, and method for facilitating input/output processing of a processing environment are provided. The computer program product is provided for performing a method including: obtaining by an input/output communications adapter of the processing environment a transport control word including an address of a channel command word descriptor configured to contain a plurality of commands to be executed by the control unit; forwarding to the control unit the channel command word descriptor that includes one or more commands as one entity, wherein the forwarding includes forwarding from the input/output communications adapter to the control unit the channel command word descriptor including the one or more commands in a single communication; and receiving the ending status by the input/output communications adapter absent a tracking of state of individual commands by the input/output communications adapter, the ending status comprising timing information associated with the one or more commands.

Claims

1. A computer program product for facilitating input/output processing of a processing environment, the computer program product comprising:

a tangible storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method comprising;

obtaining by an input/output communications adapter of the processing environment a transport control word, the transport control word including a count of the total amount of data being transferred, an address of a channel command word descriptor to be sent to a control unit of the processing environment, in which the channel command word descriptor is configured to contain a plurality of commands to be executed by the control unit, an address that informs the input/output communications adapter where to store or fetch data received from or transmitted to the control unit, and an address of a location to store ending status received from the control unit;

forwarding from the input/output communications adapter to the control unit the channel command word descriptor that includes one or more commands as one entity, wherein the forwarding includes forwarding from the input/output communications adapter to the control unit the channel command word descriptor including the one or more commands in a single communication; and

receiving the ending status by the input/output communications adapter absent a tracking of state of individual commands by the input/output communications adapter, the ending status comprising timing information associated with the one or more commands.

2. The computer program product of claim 1, wherein the timing information includes at least one of a control unit active time, a queue time and a defer time.

3. The computer program product of claim 2, wherein the control unit active time specifies an amount of time during which the control unit was actively executing the one or more commands.

4. The computer program product of claim 2, wherein the queue time indicates an amount of time during which the control unit had an I/O operation associated with the one or more commands on a queue.

5. The computer program product of claim 2, wherein the defer time indicates an amount of time during which the control unit was waiting for the data to be transferred.

6. The computer program product of claim 1, wherein the channel command word descriptor is forwarded via a Fibre Channel Protocol command information unit, and the ending status and the timing information is received via a Fibre Channel Protocol response information unit.

7. The computer program product of claim 1, wherein the channel command word descriptor includes a plurality of commands as one entity.

8. An apparatus for facilitating input/output processing of a processing environment, the apparatus comprising:

an input/output communications adapter of the processing environment configured to communicate with a control unit of the processing environment, the control unit configured to operate and control one or more I/O devices, the input/output communications adapter configured to perform a method comprising;

obtaining by the input/output communications adapter a transport control word, the transport control word including a count of the total amount of data being transferred, an address of a channel command word descriptor to be sent to the control unit, in which the channel command word descriptor is configured to contain a plurality of commands to be executed by the control unit, an address that informs the input/output communications adapter where to store or fetch data received from or transmitted to the control unit, and an address of a location to store ending status received from the control unit;

forwarding from the input/output communications adapter to the control unit the channel command word descriptor that includes one or more commands as one entity, wherein the forwarding includes forwarding from the input/output communications adapter to the control unit the channel command word descriptor including the one or more commands in a single communication; and

receiving the ending status by the input/output communications adapter absent a tracking of state of individual commands by the input/output communications adapter, the ending status comprising timing information associated with the one or more commands.

9. The apparatus of claim 8, wherein the timing information includes at least one of a control unit active time, a queue time and a defer time.

10. The apparatus of claim 9, wherein the control unit active time specifies an amount of time during which the control unit was actively executing the one or more commands.

11. The apparatus of claim 9, wherein the queue time indicates an amount of time during which the control unit had an I/O operation associated with the one or more commands on a queue.

12. The apparatus of claim 9, wherein the defer time indicates an amount of time during which the control unit was waiting for the data to be transferred.

13. The apparatus of claim 8, wherein the channel command word descriptor is forwarded via a Fibre Channel Protocol command information unit, and the ending status and the timing information is received via a Fibre Channel Protocol response information unit.

14. The apparatus of claim 8, wherein the channel command word descriptor includes a plurality of commands as one entity.

15. A method of facilitating input/output processing of a processing environment, the method comprising:

obtaining by an input/output communications adapter of the processing environment a transport control word, the transport control word including a count of the total amount of data being transferred, an address of a channel command word descriptor to be sent to a control unit of the processing environment, in which the channel command word descriptor is configured to contain a plurality of commands to be executed by the control unit, an address that informs the input/output communications adapter where to store or fetch data received from or transmitted to the control unit, and an address of a location to store ending status received from the control unit;

forwarding from the input/output communications adapter to the control unit the channel command word descriptor that includes one or more commands as one entity, wherein the forwarding includes forwarding from the input/output communications adapter to the control unit the channel command word descriptor including the one or more commands in a single communication; and

receiving the ending status by the input/output communications adapter absent a tracking of state of individual commands by the input/output communications adapter, the ending status comprising timing information associated with the one or more commands.

16. The method of claim 15, wherein the timing information includes at least one of a control unit active time, a queue time and a defer time.

17. The method of claim 16, wherein the control unit active time specifies an amount of time during which the control unit was actively executing the one or more commands.

18. The method of claim 16, wherein the queue time indicates an amount of time during which the control unit had an I/O operation associated with the one or more commands on a queue.

19. The method of claim 16, wherein the defer time indicates an amount of time during which the control unit was waiting for the data to be transferred.

20. The method of claim 15, wherein the channel command word descriptor is forwarded via a Fibre Channel Protocol command information unit, and the ending status and the timing information is received via a Fibre Channel Protocol response information unit.

21. The method of claim 15, wherein the channel command word descriptor includes a plurality of commands as one entity.