Abstract: A storage device is configured with one or more processes that receive, process, and pass on jobs from a source. The number of jobs received by a process is compared with the number of jobs completed and/or passed on by the process. If the number of jobs that are received is disproportionate to the number of jobs completed and/or passed on by the process, a hang may exist and a corrective action, such as resetting, may be performed along with a request for all or some of the jobs to be resent.

Abstract: A method, system, and program product is provided for configuring a target device, the method comprising the steps of: receiving a log-in request to connect the target device to a host, wherein the log-in request includes a host designator; accessing a table of host designators and associated O/S types; determining if there is a match of the log-in request host designator to a host designator in the table; and selecting an O/S type protocol associated with the match to the host designator. In a preferred embodiment of the present invention, the host designator is a worldwide name. In a further embodiment of the present invention, the step is provided of determining if a mode parameter is set for a default O/S protocol; and selecting that default O/S protocol unless there is a match of the log-in request host designator in the table.

Abstract: A data storage device may be constructed with a disk array; an array controller for controlling the array; and a queue for queuing commands from a host system to the disk array. Programming installed on the array controller adjusts a logical size of the queue to optimize performance.

Abstract: A data storage device may be constructed with a disk array; an array controller for controlling the array; and a queue for queuing commands from a host system to the disk array. Programming installed on the array controller adjusts a logical size of the queue to optimize performance.

Abstract: A method, system, and program product is provided for configuring a target device, the method comprising the steps of: receiving a log-in request to connect the target device to a host, wherein the log-in request includes a host designator; accessing a table of host designators and associated O/S types; determining if there is a match of the log-in request host designator to a host designator in the table; and selecting an O/S type protocol associated with the match to the host designator. In a preferred embodiment of the present invention, the host designator is a worldwide name. In a further embodiment of the present invention, the step is provided of determining if a mode parameter is set for a default O/S protocol; and selecting that default O/S protocol unless there is a match of the log-in request host designator in the table.

Abstract: It has been determined that considerable data which is written to stacks is of the type that does not require long term retention (i.e., it is only required to be valid for the duration of a procedure or function which created it). Accordingly, when a stack is employed to handle such data (and other similar data), invalidation and writes to main memory that ordinarily accompany accesses of such data (when the stack is held in a cache memory) can be avoided. The invention therefore improves memory performance by providing an overlay memory, to which is assigned a set of main memory addresses that are utilized for stack operations. When data is either read or written from/to the overlay memory, there is no further communication “downstream” to either a cache memory or main memory. In other words, the overlay memory is used for short term storage and accesses to the overlay memory are invisible to other memory elements of the system.

Abstract: 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.

Abstract: In a disk storage system having dual controllers and mirrored memory therebetween, the mirrored memory is used to establish a robust communication path between the controllers to monitor and coordinate their activities. A reserved portion of the memory in each controller is designated as a messaging mailbox which is read and written by the owning controller but only read by the remote controller. The communication protocol between the controllers is tightly coupled to insure proper messaging. Furthermore, a sliding window interlock insures message detection and correctness. In addition, interrupt signals and timer based polling are used as a dual means for detecting communication requests and replies between the controllers.