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: 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 storage system includes a backend storage unit for storing electronic information; a controller unit for controlling reading and writing to the backend storage unit; and at least one of a cache and a non-volatile storage for storing the electronic information during at least one of the reading and the writing; the controller unit executing machine readable and machine executable instructions including instructions for: testing if a frequency of non-volatile storage full condition has occurred one of above and below an upper threshold frequency value and a lower threshold frequency value; if the frequency of the condition has exceeded a threshold frequency value, then calculating a new size; calculating an expected average response time for the new size; comparing actual response time to the expected response time; and one of adjusting and not adjusting a size of the non-volatile storage to minimize the response time.