Abstract: Described is data storage system modeling. Received at a first data storage system is information representing a workload for I/O operations directed to a logical devices having storage provisioned on physical devices of a second data storage system. Information representing the workload may be obtained by performing discovery processing to discover performance characteristics of the physical devices of the second data storage system. Discovery processing may include receiving, at the first data storage system, I/O operations from a client directed to the set of one or more logical devices having storage provisioned on the physical devices of the second data storage system. The I/O operations are then issued to the second data storage system. In response, performance data is obtained at the first data storage system representing the workload for the plurality of I/O operations. Performance of the second data storage system is modeled in accordance with the workload.

Abstract: Described are techniques for tracking activity for one or more devices. Each of the one or more devices is partitioned into one or more extents. Each of the one or more extents includes a plurality of sub extents. Each of the sub extents includes a plurality of chunks. For each of said one or more extents of each of said one or more devices, extent activity level information is determined including one or more metrics indicating an activity level for said each extent; and For each of said one or more extents of each of said one or more devices, an activity bitmap is determined. The activity bitmap includes an entry for each sub extent included in said each extent, said entry indicating an activity level for said each sub extent.

Abstract: A system for normalizing capacity utilization within virtual storage pools includes collecting utilization statistics across individual storage devices that are members of a virtualized storage pool. Using the pool utilization level statistics, pool members may be assigned a score and, according to that score, may be marked as source, target or neutral members. Based on the scores of each pool member, data may be migrated among pool members, in particular, from source members to target members. The process may be iterative such that the statistics and scores may be used only to perform a fraction of the data movement that would be needed to normalize the storage pool before the scores are then recalculated. In this way, the system may dynamically adapt to changing conditions within the pool such as device additions, removals and inefficient striping of new data.

Abstract: An apparatus, program product, and method of managing entities in an object-oriented environment permit the selective inheritance of parameters or fields from parent entities and into child entities responsive to persistent indications of the inheritability of such parameters or fields stored in a non-volatile memory. Further, in many implementations, basing a determination of inheritability on such persistent information permits inheritance to be selectively restricted for a parameter or field without requiring any changes to the database schema for a database that controls access to the parent and child entities.

Abstract: A platen holder for a hot press printing machine has a framework for attachment to the machine. On the framework is pivotally supported a platen receiver in which a platen holder is slidably mounted. The receiver is pivoted into an inverted position for providing easy access to a type block carried by the platen.