Abstract: Host input/output (I/O) operations are performed via a file stored in a non-volatile storage coupled to a storage controller while data structures are being generated in the storage controller to copy data from source logical volumes to target logical volumes. The source logical volumes and the target logical volumes are logical representations of physical storage maintained in a plurality of direct access storage devices. The contents of the file are transferred from the non-volatile storage to one or more of the plurality of direct access storage devices, after the data structures have been generated, wherein the host I/O operations are performed via the file while the contents of the file are being transferred to the one or more of the plurality of direct access storage devices. The host I/O operations to the plurality of direct access storage devices are resumed, in response to transferring entire contents of the file to the one or more of the plurality of direct access storage devices.

Abstract: A method for determining power consumption in a data storage system is provided. The method comprises determining data access patterns for at least a first storage device in a storage system based on operations performed by the first storage device; and calculating power consumption for the storage system by interpolating costs associated with the operations performed by the first storage device, wherein the cost associated with each operation is determined based on: (1) various levels of activities for the first storage device and a mix of workload characteristics, and (2) predetermined power consumption measurements obtained from one or more benchmarks for same operations performed by a second storage device in a test environment.

Abstract: An apparatus, system and method to optimize load distribution across logical and physical resources in a storage system. An apparatus in accordance with the invention may include an availability module and an allocation module. The availability module may dynamically assign values to resources in a hierarchical tree structure. Each value may correspond to an availability parameter such as allocated volumes, current resource utilization, and historic resource utilization. The allocation module may serially process the values and allocate a load to a least busy resource in the hierarchical tree structure based on the assigned values.

Abstract: Provided are techniques for introducing a delay in responding to host write requests. A percentage of fullness of a write cache is determined. Based on the determined percentage of fullness of the write cache (f), a low cache threshold (L), alpha (?), and k, an amount of delay to introduce into responding to a host write request is determined. Techniques wait the amount of the delay before responding to the host write request although the host write request processing has completed.

Abstract: Provided are techniques for introducing a delay in responding to host write requests. A percentage of fullness of a write cache is determined. Based on the determined percentage of fullness of the write cache (f), a low cache threshold (L), alpha (?), and k, an amount of delay to introduce into responding to a host write request is determined. Techniques wait the amount of the delay before responding to the host write request although the host write request processing has completed.

Abstract: Provided are techniques for transmitting blocks of data. It is determined whether any high priority out of sync (HPOOS) indicator is set to indicate that a number of modified segments associated with a block of data are less than or equal to a modified segments threshold. In response to determining that at least one high priority out of sync indicator is set, one or more sub-blocks of data in the modified segments associated with the block of data and with one set high priority out of sync indicator are transferred.

Abstract: A method for determining power consumption in a data storage system is provided. The method comprises determining data access patterns for at least a first storage device in a storage system based on operations performed by the first storage device; and calculating power consumption for the storage system by interpolating costs associated with the operations performed by the first storage device, wherein the cost associated with each operation is determined based on: (1) various levels of activities for the first storage device and a mix of workload characteristics, and (2) predetermined power consumption measurements obtained from one or more benchmarks for same operations performed by a second storage device in a test environment.

Abstract: Host input/output (I/O) operations are performed via a file stored in a non-volatile storage coupled to a storage controller while data structures are being generated in the storage controller to copy data from source logical volumes to target logical volumes. The source logical volumes and the target logical volumes are logical representations of physical storage maintained in a plurality of direct access storage devices. The contents of the file are transferred from the non-volatile storage to one or more of the plurality of direct access storage devices, after the data structures have been generated, wherein the host I/O operations are performed via the file while the contents of the file are being transferred to the one or more of the plurality of direct access storage devices. The host I/O operations to the plurality of direct access storage devices are resumed, in response to transferring entire contents of the file to the one or more of the plurality of direct access storage devices.

Abstract: An apparatus, system and method to optimize load distribution across logical and physical resources in a storage system. An apparatus in accordance with the invention may include an availability module and an allocation module. The availability module may dynamically assign values to resources in a hierarchical tree structure. Each value may correspond to an availability parameter such as allocated volumes, current resource utilization, and historic resource utilization. The allocation module may serially process the values and allocate a load to a least busy resource in the hierarchical tree structure based on the assigned values.

Abstract: Provided are techniques for transmitting blocks of data. It is determined whether any high priority out of sync (HPOOS) indicator is set to indicate that a number of modified segments associated with a block of data are less than or equal to a modified segments threshold. In response to determining that at least one high priority out of sync indicator is set, one or more sub-blocks of data in the modified segments associated with the block of data and with one set high priority out of sync indicator are transferred.

Abstract: Provided are techniques for transmitting blocks of data. It is determined whether any high priority out of sync (HPOOS) indicator is set to indicate that a number of modified segments associated with a block of data are less than or equal to a modified segments threshold. In response to determining that at least one high priority out of sync indicator is set, one or more sub-blocks of data in the modified segments associated with the block of data and with one set high priority out of sync indicator are transferred.