System and method for handling I/O requests over an interface bus to a storage disk array

摘要

A multi-tasking, multi-initiator computing system includes an interfacing bus, at least one storage disk array connected to the interfacing bus, and multiple initiators connected to the interfacing bus to request I/O processes to be performed by the storage disk array. A disk array controller is provided in the storage disk array to assign the I/O requests received from the initiators to one of two types of job control data structures: (1) regular job control data structures that hold the information to process and complete the I/O request, and (2) minimized job control data structures that are temporarily used when no regular job control data structures are available. The disk array controller assigns the I/O request to the minimized job control data structures only in the event that no free regular job control data structures are available to hold the information from the I/O request. Each minimized job control data structure holds a subset of the information from the I/O request that is sufficient to reinitiate the I/O request for completion when a regular job control data structure once again becomes available. A method for operating a computing system and a memory data structure are also described.