Method and system for incremental time zero backup copying of data

• US RE37,601 E1
• Filed: 11/15/1995
• Issued: 03/19/2002
• Est. Priority Date: 04/20/1992
• Status: Expired due to Term

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Eastridge, Lawrence Elwood, Kern, Robert Frederic, Ratliff, James Mitchell
• Primary Examiner(s): Decady, Albert
• Assistant Examiner(s): Ton, David
• Application Number:
  US08/559,509
• Time in Patent Office: 2,316 Days
• Field of Search: 395/425, 395/182.04, 395/182.13, 364/268.1, 364/268.3, 714/6, 711/162, 711/114, 711/100
• US Class Current: 714/6.3
• CPC Class Codes: G06F 11/1451 by selection of backup contents
• CPC Class Codes: G06F 11/1461 Backup scheduling policy
• CPC Class Codes: G06F 11/1466 to make the backup process non-disruptive

Abstract

Backup copying of designated datasets representing a first selected point in time consistency may be performed in a data processing system on an attached storage subsystem concurrent with data processing system application execution by first suspending application execution only long enough to form a logical-to-physical address concordance, and thereafter physically backing up the datasets on the storage subsystem on a scheduled or opportunistic basis. An indication of each update to a selected portion of the designated datasets which occurs after the first selected point in time is stored and application initiated updates to uncopied designated datasets are first buffered. Thereafter, sidefiles are made of the affected datasets, or portions thereof, the updates are then written through to the storage subsystem, and the sidefiles written to an alternate storage location in backup copy order, as controlled by the address concordance. At a subsequent point in time only those portions of the designated datasets which have been updated after the first selected period and time are copied, utilizing an identical technique.

Claims

1. A method in a data processing system for incremental backup copying of designated datasets stored within one or more storage subsystems coupled to said data processing system during application execution within said data processing system, said method comprising the steps of:

suspending application execution within said data processing system at a first point in time, forming a dataset logical-to-physical storage system address concordance for said designated datasets and resuming application execution thereafter;

physically backing up said designated datasets within said one or more storage subsystems on a scheduled or opportunistic basis by copying said designated datasets from said one storage subsystems to alternate storage subsystem locations;

storing an indication of each application initiated update to said designated datasets which occurs after said first point in time;

processing at said one or more storage subsystems any application initiated updates to uncopied designated datasets by buffering said updates, writing sidefiles of said designated datasets or portions thereof affected by said updates, writing said updates to said one or more storage subsystems, and copying on a scheduled or opportunistic basis said sidefiles to said alternate storage subsystem location in conjunction with said copied designated datasets from said one more storage subsystems in an order defined by said address concordance; and

creating an incremental backup copy of said designated datasets at a designated time subsequent to said first point in time by copying only those designated datasets or portions thereof updated after said first point in time.

2. The method in a data processing system for incremental backup copying of designated datasets stored within one or more storage subsystems coupled to said data processing system according to claim 1, wherein said step of creating an incremental backup copy of said designated datasets comprises the steps of:

forming a second dataset logical-to-physical storage system address concordance at said designated time for each designated dataset or portion thereof updated after said first point in time;

physically backing up said designated datasets updated after said first point in time on a scheduled or opportunistic basis by copying said designated datasets updated after said first point in time from said one or more storage subsystems to alternate storage subsystem locations; and

processing at said one more storage subsystems any application initiated updates to uncopied designated datasets previously updated after said first point in time by buffering said updates, writing sidefiles of said designated datasets of portions thereof affected by said updates, writing said updates to said one or more storage subsystems, and copying on a scheduled or opportunistic basis said sidefiles to said alternate storage location in conjunction with said copied designated datasets in an order defined by said second address concordance.

3. A method in a data processing system for incremental backup copying of designated datasets stored within one or more tracked cyclic storage devices coupled to said data processing system during application execution within said data processing system, said method comprising the steps of:

suspending application execution within said data processing system at a first point in time in response to a request for a backup copy of at least one dataset stored within said one or more tracked cyclic storage devices;

forming a dataset and device track concordance for said at least one dataset and signaling said data processing system of the completion thereof;

resuming application execution within said data processing system in response to said completion signal;

copying said at least one dataset from said one or more tracked cyclic storage devices on a scheduled or opportunistic basis to an alternate storage subsystem;

storing an indication of each application initiated update to any portion of said at least one dataset which occurs after said first point in time;

processing application initiated updates to uncopied portions of said at least one dataset by buffering said updates, writing sidefiles of said affected portions of said at least one dataset, writing said updates to said one or more tracked cyclic storage devices and copying said sidefiles to said alternate storage location; and

creating an incremental backup copy of said at least one dataset at a designated time subsequent to said first point in time by copying to said alternate storage system location only those portions of said at least one dataset which have been updated after said first point in time.

4. A data processing system for performing incremental backup copying of designated datasets stored within one or more storage subsystems coupled to said data processing subsystem during application execution within said data processing system, said data processing system comprising:

means for suspending application execution within said data processing system at a first point in time;

means for forming a dataset logical-to-physical storage system address concordance for said designated datasets at said first point in time;

means for resuming application execution thereafter;

means for physically backing up said designated datasets within said one or more storage subsystems on a scheduled or opportunistic basis by copying said designated datasets from said one storage subsystems to alternate storage subsystem locations;

means for storing an indication of each application initiated update to said designated datasets which occurs after said first point in time;

means for processing at said one or more storage subsystems any application initiated updates to uncopied designated datasets by buffering said updates, writing sidefiles of said designated datasets or portions thereof affected by said updates, writing said updates to said one or more storage subsystems, and copying on a scheduled or opportunistic basis said sidefiles to said alternate storage subsystem location in conjunction with said copied designated datasets from said one more storage subsystems in an order defined by said address concordance; and

means for creating an incremental backup copy of said designated datasets at a designated time subsequent to said first point in time by copying only those designated datasets or portions thereof updated after said first point in time.

5. A storage control unit having a cache memory for permitting incremental backup copying of designated datasets stored within a storage subsystem associated therewith by a data processing system coupled thereto, said storage control unit comprising:

means for forming a dataset logical-to-physical storage address concordance for said designated datasets within said storage subsystem at a first point in time;

means for permitting copying of said designated datasets within said stored designated datasets on a scheduled or opportunistic basis by said data processing system;

means for storing an indication of each update to a portion of said designated datasets which occurs after said first point in time;

means for processing updates to uncopied portions of said designated datasets by buffering said updates, writing sidefiles of said uncopied portions of said designated datasets affected by said updates within said cache memory and writing said updates into said associated storage subsystems;

means for permitting copying of said sidefiles by said data processing system; and

means for permitting selective copying at a designated time after said first point in time of said portions of said designated datasets updated after said first point in time.

6. A computer program product for use in a data processing system for incremental backup copying of designated datasets stored within one or more data storage subsystems coupled to the data processing system during application execution within the data processing system, said computer program product comprising:

computer usable code means for suspending application execution within said data processing system at a first point in time, forming a dataset logical-to-physical storage system address concordance for said designated datasets and resuming application execution thereafter;

7. The computer program product for use in a data processing system for incremental backup copying of designated datasets stored within one or more storage subsystems coupled to said data processing system according to claim 6, wherein said step code means of creating an incremental backup copy of said designated datasets comprises:

computer usable code means for forming a second dataset logical-to-physical storage system address concordance at said designated time for each designated dataset or portion thereof updated after said first point in time;

8. A computer program product for use in a data processing system for incremental backup copying of designated datasets stored within one or more tracked cyclic storage devices coupled to the data processing system during application execution within the data processing system, said computer program product comprising:

9. A computer program product for performing incremental backup copying of designated datasets stored within one or more storage subsystems coupled to a data processing subsystem during application execution within a data processing system, said computer program product comprising:

10. A computer program product for permitting incremental backup copying of designated datasets stored within a storage subsystem with a data processing system, said computer program product comprising:

computer usable code means for forming a dataset logical-to-physical storage address concordance for said designated datasets within said storage subsystem at a first point in time;