Executing host data transfer operations during setup of copy services operations

摘要

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.

主权项

1. A method, comprising:
storing only those tracks that are affected by a copy services action in a file, during a copy services setup time; determining, via a processor, whether a copy services setup is active; in response to determining that the copy services setup is active, performing: in response to a read request from a host for selected data, returning the selected data from the file if the file includes the selected data; and in response to determining that the copy services setup is not active, performing: determining whether the file is empty, and in response to determining that the file is not empty, in response to the read request from the host for the selected data, returning the selected data from the file if the file includes the selected data.