Abstract: Systems and methods for implementing device loading in storage networks are disclosed. In an exemplary implementation a computer program product encodes a computer program for executing on a computer system a computer process. The computer process comprises identifying a plurality of storage devices to be configured in a storage network, identifying a number of host port LUNs configured on each of the storage devices, and identifying a number of host port connections to the storage devices. For each host port connection, the computer process determines actual loading for each of the storage devices based at least in part on the queue depth for each of the host port LUNs.

Abstract: Systems and methods for adjusting the number of tasks that are accepted for processing in a computer based on processing resources required by the tasks, processing resources available in the computer system, and the time allowed to complete at least one of the tasks. The tasks that are accepted for processing can be scheduled to timeshare the processing resources available so that the task(s) complete within the time allowed.

Abstract: A method for processing a fiber channel (FC) layer service request at a target node of an FC network may include receiving the FC layer service request from an initiator node, extracting a permanent identifier and a temporary identifier from the received FC layer service request, and determining whether a match exists between the extracted temporary identifier and a temporary identifier stored in association with the extracted permanent identifier. A security access device and computer-readable code arrangement may include similar features.

Abstract: In certain, currently available data-storage systems, incoming commands from remote host computers are subject to several levels of command-queue-depth-fairness-related throttles to ensure that all host computers accessing the data-storage systems receive a reasonable fraction of data-storage-system command-processing bandwidth to avoid starvation of one or more host computers. Recently, certain host-computer-to-data-storage-system communication protocols have been enhanced to provide for association of priorities with commands. However, these new command-associated priorities may lead to starvation of priority levels and to a risk of deadlock due to priority-level starvation and priority inversion. In various embodiments of the present invention, at least one additional level of command-queue-depth-fairness-related throttling is introduced in order to avoid starvation of one or more priority levels, thereby eliminating or minimizing the risk of priority-level starvation and priority-related deadlock.

Abstract: In certain, currently available data-storage systems, incoming commands from remote host computers are subject to several levels of command-queue-depth-fairness-related throttles to ensure that all host computers accessing the data-storage systems receive a reasonable fraction of data-storage-system command-processing bandwidth to avoid starvation of one or more host computers. Recently, certain host-computer-to-data-storage-system communication protocols have been enhanced to provide for association of priorities with commands. However, these new command-associated priorities may lead to starvation of priority levels and to a risk of deadlock due to priority-level starvation and priority inversion. In various embodiments of the present invention, at least one additional level of command-queue-depth-fairness-related throttling is introduced in order to avoid starvation of one or more priority levels, thereby eliminating or minimizing the risk of priority-level starvation and priority-related deadlock.

Abstract: A method for processing a fibre channel (FC) layer service request at a target node of an FC network may include receiving the FC layer service request from an initiator node, extracting a permanent identifier and a temporary identifier from the received FC layer service request, and determining whether a match exists between the extracted temporary identifier and a temporary identifier stored in association with the extracted permanent identifier. A security access device and computer-readable code arrangement may include similar features.

Abstract: A hardware-based mirroring agent that provides a LUN-based I/O interface to remote host computers, including mirrored LUNs, implemented via remote data storage devices. The hardware-based mirroring agent is similar to a disk array, but manages and provides to host computers an interface to remote data storage devices, rather than to internal data storage devices, as in the case of disk arrays.

Abstract: A hardware-based mirroring agent that provides a LUN-based I/O interface to remote host computers, including mirrored LUNs, implemented via remote data storage devices. The hardware-based mirroring agent is similar to a disk array, but manages and provides to host computers an interface to remote data storage devices, rather than to internal data storage devices, as in the case of disk arrays.

Abstract: The inventive state mechanism assigns N+1 tags to N versions of an object stored in N memory areas. Thus, one tag is unused. An additional tag is used as a null or uninitialized tag. The other tags are assigned in a particular precedence order to revisions as they are stored. Thus, each assigned tag, except the null tag, has both a unique predecessor as well as a unique successor tag. The last tag of the sequence is lower in precedence to the first tag of the sequence, and this forms the cyclic relationship. The unused tag is used to determine the tag that is to be assigned to the next revision. The unused tag is also used to determine which revision is the most current revision. The inventive state mechanism is used by a memory management controller in maintaining the revisions.