Inter-adapter cooperation for multipath input/output systems

1. A method comprising:

dynamically sharing information between or among a plurality of adapters in a multipath input/output system;

responsive to the shared information, selecting, from the plurality of adapters in the multipath input/output system, a first adapter to service an input/output request for transferring data from a source to a destination; and

responsive to the selection, sending the input/output request to the first adapter;

wherein:

each adapter in the plurality of adapters lies along one or more paths between the source and the destination; and

the adapters in the plurality of adapters provide mutually exclusive alternatives for servicing the input/output request.

2. The method of claim 1 wherein the shared information includes status information of the adapters in the plurality of adapters.

3. The method of claim 1 wherein the shared information includes a shared queue that contains the input/output request.

4. The method of claim 1 wherein the adapters in the plurality of adapters are virtual adapters.

5. The method of claim 2 further comprising:

computing an adapter priority for the first adapter based, at least in part, on the shared status information.

6. The method of claim 5 wherein the shared status information includes the computed adapter priority.

7. A computer program product comprising a non-transitory computer readable storage medium having stored thereon:

first program instructions programmed to dynamically share information between or among a plurality of adapters in a multipath input/output system;

second program instructions programmed to, responsive to the shared information, select, from the plurality of adapters in the multipath input/output system, a first adapter to service an input/output request for transferring data from a source to a destination; and

third program instructions programmed to, responsive to the selection, send the input/output request to the first adapter;

wherein:

each adapter in the plurality of adapters lies along one or more paths between the source and the destination; and

the adapters in the plurality of adapters provide mutually exclusive alternatives for servicing the input/output request.

8. The product of claim 7 wherein the shared information includes status information of the adapters in the plurality of adapters.

9. The product of claim 7 wherein the shared information includes a shared queue that contains the input/output request.

10. The product of claim 7 wherein the adapters in the plurality of adapters are virtual adapters.

11. The product of claim 8 having further stored thereon:

fourth program instructions programmed to compute an adapter priority for the first adapter based, at least in part, on the shared status information.

12. The product of claim 11 wherein the shared status information includes the computed adapter priority.

13. A computer system comprising:

a processor(s) set; and

a computer readable storage medium;

wherein:

the processor set is structured, located, connected and/or programmed to run program instructions stored on the computer readable storage medium; and

the program instructions include:

first program instructions programmed to dynamically share information between or among a plurality of adapters in a multipath input/output system;

second program instructions programmed to, responsive to the shared information, select, from the plurality of adapters in the multipath input/output system, a first adapter to service an input/output request for transferring data from a source to a destination; and

third program instructions programmed to, responsive to the selection, send the input/output request to the first adapter;

wherein:

each adapter in the plurality of adapters lies along one or more paths between the source and the destination; and

the adapters in the plurality of adapters provide mutually exclusive alternatives for servicing the input/output request.

14. The system of claim 13 wherein the shared information includes status information of the adapters in the plurality of adapters.

15. The system of claim 13 wherein the shared information includes a shared queue that contains the input/output requests.

16. The system of claim 13 wherein the adapters in the plurality of adapters are virtual adapters.

17. The system of claim 16 wherein the program instructions further include:

fourth program instructions programmed to compute an adapter priority for the first adapter based, at least in part, on the shared status information.

18. The system of claim 17 wherein the shared status information includes the computed adapter priority.