Method and system for sidefile status polling in a time zero backup copy process

A data processing system for enhanced efficiency of backup copying of designated datasets stored within a storage subsystem comprising a plurality of storage devices which are coupled to said data processing system via a storage device control unit having subsystem memory therein, said data processing system comprising:

• means for forming a dataset logical-to-physical system address concordance for said designated datasets to be utilized to administer copying of said designated datasets;
• means for processing at said storage subsystem any application initiated update to uncopied portions of said designated datasets by temporarily deferring said updates, writing sidefiles of said designated datasets or portions thereof affected by said update to said subsystem memory and thereafter writing said updates to said storage subsystem;
• means for accessing and copying said designated datasets within said storage subsystem on a scheduled or opportunistic basis by issuing data retrieval command sequences from said data processing system to said storage subsystems;
• means for periodically appending a sidefile status query to a data retrieval command sequence wherein a determination of data presence within said subsystem memory may be accomplished;
• and
• means for selectively accessing and copying said sidefiles in response to a determination of data presence within said subsystem memory.

A method in a data processing system for enhanced efficiency of backup copying of designated datasets stored within a storage subsystem comprising a plurality of storage devices which are coupled to said data processing system via a storage device control unit having subsystem memory therein, said method comprising the steps of:

• forming a dataset logical-to-physical system address concordance for said designated datasets to be utilized to administer copying of said designated datasets;
• processing at said storage subsystem any application initiated updated to uncopied portions of said designated datasets by temporarily deferring said updates, writing sidefiles of said designated datasets or portions thereof affected by said update to said subsystem memory and thereafter writing said updates to said storage subsystem;
• accessing and copying said designated datasets within said storage subsystem on a scheduled or opportunistic basis by issuing data retrieval command sequences from said data processing system to said storage subsystems;
• periodically issuing a sidefile status query to determine the status of data within said subsystem memory;
• and
• selectively accessing and copying said sidefiles in response to a determination of data presence within said subsystem memory.

A data processing system for enhanced efficiency of backup copying of designated datasets stored within a storage subsystem comprising a plurality of storage devices which are coupled to said data processing system via a storage device control unit having subsystem memory therein, said data processing system comprising:

• means for forming a dataset logical-to-physical system address concordance for said designated datasets to be utilized to administer copying of said designated datasets;
• means for processing at said storage subsystem any application initiated update to uncopied portions of said designated datasets by temporarily deferring said updates, writing sidefiles of said designated datasets or portions thereof affected by said update to said subsystem memory and thereafter writing said updates to said storage subsystem;
• means for accessing and copying said designated datasets within said storage subsystem on a scheduled or opportunistic basis by issuing data retrieval command sequences from said data processing system to said storage subsystems;
• means for periodically issuing a sidefile status query to determine the status of data within said subsystem memory;
• and
• means for selectively accessing and copying said sidefiles in response to a determination of data presence within said subsystem memory.

A computer program product for use in a data processing system for enhanced efficiency of backup copying of designated datasets stored within a storage subsystem coupled to said data processing system via a storage device control unit having subsystem memory therein, said product comprising:

• instruction means for forming a dataset logical-to-physical system address concordance for said designated datasets to be utilized to administer copying of said designated datasets;
• instruction means for processing at said storage subsystem any application initiated update to uncopied portions of said designated datasets by temporarily deferring said updates, writing sidefiles of said designated datasets or portions thereof affected by said update to said subsystem memory and thereafter writing said updates to said storage subsystem;
• instruction means for accessing and copying said designated datasets within said storage subsystem on a scheduled or opportunistic basis by issuing data retrieval command sequences from said data processing system to said storage subsystem;
• instruction means for periodically appending a sidefile status query to a data retrieval command sequence wherein a determination of data presence within said subsystem memory may be accomplished;
• and
• instruction means for selectively accessing and copying said sidefiles in response to a determination of data presence within said subsystem memory.

A computer program product for use in a data processing system for enhanced efficiency of backup copying of designated datasets stored within a storage subsystem coupled to said data processing system via a storage device control unit having subsystem memory therein, said product comprising:

• instruction means for forming a dataset logical-to-physical system address concordance for said designated datasets to be utilized to administer copying of said designated datasets;
• instruction means for processing at said storage subsystem any application initiated update to uncopied portions of said designated datasets by temporarily deferring said updates, writing sidefiles of said designated datasets or portions thereof affected by said update to said subsystem memory and thereafter writing said updates to said storage subsystem;
• instruction means for accessing and copying said designated datasets within said storage subsystem on a scheduled or opportunistic basis by issuing data retrieval command sequences from said data processing system to said storage subsystem;
• instruction means for periodically issuing a sidefile status query to determine the status of data within said subsystem memory;
• and
• instruction means for selectively accessing and copying said sidefiles in response to a determination of data presence within said subsystem memory.