US 5,497,483 A · Method and system for track transfer control during concurrent copy operations in a data processing storage subsystem

Abstract

A method and system are disclosed for transferring backup copies of designated multi-track datasets which are stored in a plurality of storage subsystems to a host system via data channel during concurrent execution of an application. Upon receiving a request for a backup copy, execution of an application is temporarily suspended. A dataset logical-to-physical storage system address concordance is formed and execution of the application is resumed thereafter. Any application initiated updates to affected tracks within the designated datasets which occur prior to generation of a backup copy are processed by buffering the updates, copying the affected tracks to storage subsystem memory, updating the address concordance and writing the updates to the affected tracks within the dataset. Requests from the host system to transfer a selected sequence of tracks within the designated multi-track dataset are then examined to determine if the sequence includes affected tracks which have previously been copied to storage subsystem memory. An artificial track is then automatically substituted into the requested sequence of selected tracks for each affected track which has previously been copied to storage subsystem memory during transfer of the selected sequence of tracks such that the host system is made aware of the previous copying of these affected tracks.

Claims12

Dependent claims

A method in a data processing system for transferring a backup copy of multiple tracks within designated datasets stored in a plurality of storage subsystems to a host system via a data channel during concurrent execution of an application within said host system wherein each of said storage subsystems includes storage subsystem memory associated therewith, said method comprising the steps of:

suspending execution of said application in response to a request for generating a backup copy;
forming a dataset logical-to-physical storage subsystem address concordance for said designated datasets;
resuming execution of said application upon completion of said forming of said address concordance;
processing any application initiated updates to tracks affected by said updates within said designated datasets which updates occur prior to generation of a backup copy of said tracks affected by said updates within said designated datasets by buffering said updates, copying said tracks affected by said updates within said designated datasets to said storage subsystem memory, updating said address concordance in response to said copying, and writing said updates to said tracks affected by said updates within said designated datasets within said plurality of storage subsystems;
utilizing said address concordance in response to a request from said host system to transfer a portion of said designated datasets which includes a sequence of selected tracks to determine if said sequence of selected tracks includes tracks affected by said updates which have been previously copied to said storage subsystem memory;
and
automatically substituting an artificial track into said sequence of selected tracks in place of each track affected by said updates which has been previously copied to storage subsystem memory during transfer of said portion of said designated datasets to said host system.

4 more elements

A data processing system for transferring a backup copy of multiple tracks within designated datasets stored in a plurality of storage subsystems to a host system via a data channel during concurrent execution of an application within said host system wherein each of said storage subsystems includes storage subsystem memory associated therewith, said data processing system comprising:

means for suspending execution of said application in response to a request for generating a backup copy;
means for forming a dataset logical-to-physical storage subsystem address concordance for said designated datasets;
means for resuming execution of said application upon completion of said forming of said address concordance;
means for processing any application initiated updates to tracks affected by said updates within said designated datasets which updates occur prior to generation of a backup copy of said tracks affected by said updates of said designated datasets by buffering said updates, copying said tracks affected by said updates of said designated datasets to said storage subsystem memory, updating said address concordance in response to said copying, and writing said updates to said affected tracks of said designated datasets within said plurality of storage subsystems;
means for utilizing said address concordance in response to a request from said host system to transfer a portion of said designated datasets which includes a sequence of selected tracks to determine if said sequence of selected tracks includes tracks affected by said updates which have been previously copied to said storage subsystem memory;
and
means for automatically substituting an artificial track into said sequence of selected tracks in place of each track affected by said updates which has been previously copied to storage subsystem memory during transfer of said portion of said designated datasets to said host system.

4 more elements

Dependencies are inferred from the claim text.

Method and system for track transfer control during concurrent copy operations in a data processing storage subsystem

Life of this patent

Method and system for track transfer control during concurrent copy operations in a data processing storage subsystem

Life of this patent

Abstract

Claims12