US5381545A
Expired / Lapsed
US
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Data backup and recovery in a data processing system
Assignee: International Business Machines Corp
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Filing: 1992-05-28
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Granted: 1995-01-10
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Expires: 2012-05-28
Abstract
Abstract A data processing system for managing stored data is described. A log recording incremental updates to the data is provided for data recovery purposes in the event of a system failure. A backup copy of at least a portion of the stored data can be made without closing that portion for update. Any in-progress modifications at the time the backup is taken are allowed for by calculating a recovery point before the time of the backup, from which point recovery is to be performed using the recovery log. The recovery point depends at least in part on the start time of the oldest in-progress data file update.
Inventors
- 👤 Stephen M. Baker
- 👤 Peter J. Lupton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 21:30
CPC Classifications
G; G06; G06F; G06F11/00; G06F11/07; G06F11/14; G06F11/1446; G06F11/1448; G06F11/1451; G06F11/1458; G06F11/1466; G06F11/1471; Y; Y10; Y10S; Y10S707/00; Y10S707/99951; Y10S707/99952; Y10S707/99953
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
124 words
Data processing apparatus comprising: means for processing stored data as a series of logical units of work (LUWs), with updates to the stored data made during each LUW being committed at a commit point for that LUW; means for maintaining a log of updates made to the stored data: means for detecting the oldest uncommitted update made to the stored data; means responsive to the detecting means for calculating a recovery point; means for taking a backup copy of at least a portion of the stored data while that portion is available for update; and means for recovering the database by reinstating the backup copy to provide a working copy and applying the updates contained in any log entries made after said recovery point.
Claim 2
Dependent Claim
124 words
Data processing apparatus comprising: means for processing stored data as a series of logical units of work (LUWs), with updates to the stored data made during each LUW being committed at a commit point for that LUW; means for maintaining a log of updates made to the stored data: means for detecting the oldest uncommitted update made to the stored data; means responsive to the detecting means for calculating a recovery point; means for taking a backup copy of at least a portion of the stored data while that portion is available for update; and means for recovering the database by reinstating the backup copy to provide a working copy and applying the updates contained in any log entries made after said recovery point.
Claim 3
Dependent Claim
75 words
Data processing apparatus as claimed in claim 1, in which the means for detecting the oldest uncommitted update comprises: means for detecting the first log entry, corresponding to an update, made by each LUW; means for storing the time of that first log entry; means for detecting the earliest of at least a subset of the stored first log entry times; and means for deleting the first log entry time corresponding to a completed LUW.
Claim 4
Dependent Claim
32 words
Data processing apparatus of claim 1, in which: the stored data is organized as a plurality of data sets, each data set being addressable by means of one or more alias filenames.
Claim 5
Dependent Claim
61 words
Data processing apparatus as claimed in claim 3, in which: each data set has an associated catalogue, for storing system housekeeping data; and the recovery point corresponding to a data set is written to that data set's catalogue; and the backup copy of a data set includes a copy of the data set's catalogue at the time the backup was taken.
Claim 6
Dependent Claim
38 words
Data processing apparatus as claimed in claim 3 or claim 4, further comprising: means for associating with a data set a data item signifying whether that data set is eligible to be backed up while available for update.
Claim 7
Dependent Claim
40 words
Data processing apparatus of claim 3, further comprising: means for writing a tie-up-record (TUR) to the log when a filename is associated with a data set, the TUR defining at least the association between the filename and the data set.
Claim 8
Dependent Claim
29 words
Data processing apparatus as claimed in claim 6, further comprising: means for periodically writing to the log a set of TURs for at least some of the data sets.
Claim 9
Dependent Claim
32 words
Data processing apparatus as claimed in claim 7, in which: the set of TURs comprises those TURs corresponding to filenames associated with open data sets eligible to be backed up while open.
Claim 10
Dependent Claim
37 words
Data processing apparatus as claimed in claim 7, in which: the recovery point is defined as the start time of writing a previous set of TURs for which writing completed before the oldest uncommitted update was made.
Claim 11
Dependent Claim
24 words
Data processing apparatus of claim 7, in which: a recovery point is calculated when a set of TURs has been written to the log.
Claim 12
Dependent Claim
25 words
Data processing apparatus of claim 1, in which: the recovery point corresponding to a backup copy is calculated at the time that backup is taken.
Claim 13
Dependent Claim
35 words
Data processing apparatus of claim 1, in which the recovery point associated with the backup copy is equal to the start time of the oldest uncommitted updated at the time the backup copy was made.
Claim 14
Independent Claim
127 words
A method of operation of a data processor, comprising the steps of: processing stored data as a series of logical units of work (LUWs), with updates to the stored data made during each LUW being committed at a commit point for that LUW; maintaining a log of updates made to the stored data; detecting the oldest uncommitted update made to the stored data; calculating a recovery point dependent upon the start time of the oldest uncommitted update; taking a backup copy of at least a portion of the stored data while that portion is available for update; and when necessary, recovering the database by reinstating the backup copy to provide a working copy and applying the updates contained in any log entries made after said recovery point.
Claim 15
Independent Claim
127 words
A method of operation of a data processor, comprising the steps of: processing stored data as a series of logical units of work (LUWs), with updates to the stored data made during each LUW being committed at a commit point for that LUW; maintaining a log of updates made to the stored data; detecting the oldest uncommitted update made to the stored data; calculating a recovery point dependent upon the start time of the oldest uncommitted update; taking a backup copy of at least a portion of the stored data while that portion is available for update; and when necessary, recovering the database by reinstating the backup copy to provide a working copy and applying the updates contained in any log entries made after said recovery point.
Claim 16
Dependent Claim
124 words
A transaction management system having means for processing stored data as a series of logical units of work (LUWs), with updates to the stored data made during each LUW being committed at a commit point for that LUW; means for maintaining a log of updates made to the stored data; means for detecting the oldest uncommitted update made to the stored data: means responsive to the detecting means for calculating a recovery point; means for taking a backup copy of at least a portion of the stored data while that portion is available for update; and means for recovering the database by reinstating the backup to provide a working copy and applying the updates contained in any log entries made after said recovery point.
Claim 17
Dependent Claim
124 words
A transaction management system having means for processing stored data as a series of logical units of work (LUWs), with updates to the stored data made during each LUW being committed at a commit point for that LUW; means for maintaining a log of updates made to the stored data; means for detecting the oldest uncommitted update made to the stored data: means responsive to the detecting means for calculating a recovery point; means for taking a backup copy of at least a portion of the stored data while that portion is available for update; and means for recovering the database by reinstating the backup to provide a working copy and applying the updates contained in any log entries made after said recovery point.
Claim 18
Dependent Claim
124 words
A transaction manager, for cooperating with a data processing apparatus, to provide means for processing stored data as a series of logical units of work (LUWs), with updates to the stored data made during each LUW being committed at a commit point for that LUW; maintaining a log of updates made to the stored data; detecting the oldest uncommitted update made to the stored data; calculating a recovery point dependent upon the start time of the oldest uncommitted update; taking a backup copy of at least a portion of the stored data while that portion is available for update; and when necessary, recovering the database by reinstating the backup copy and applying the updates contained in any log entries made after said recovery point.
Claim 19
Dependent Claim
124 words
A transaction manager, for cooperating with a data processing apparatus, to provide means for processing stored data as a series of logical units of work (LUWs), with updates to the stored data made during each LUW being committed at a commit point for that LUW; maintaining a log of updates made to the stored data; detecting the oldest uncommitted update made to the stored data; calculating a recovery point dependent upon the start time of the oldest uncommitted update; taking a backup copy of at least a portion of the stored data while that portion is available for update; and when necessary, recovering the database by reinstating the backup copy and applying the updates contained in any log entries made after said recovery point.
Claim 20
Dependent Claim
125 words
Apparatus cooperable with data processing apparatus to provide means for processing stored data as a series of logical units of work (LUWs), with updates to the stored data made during each LUW being committed at a commit point for that LUW; maintaining a log of updates made to the stored data; detecting the oldest uncommitted update made to the stored data; calculating a recovery point dependent upon the start time of the oldest uncommitted update: taking a backup copy of at least a portion of the stored data while that portion is available for update; and when necessary, recovering tile database by reinstating the backup copy to provide a working copy and applying the updates contained in any log entries made after said recovery point.
Claim 21
Dependent Claim
125 words
Apparatus cooperable with data processing apparatus to provide means for processing stored data as a series of logical units of work (LUWs), with updates to the stored data made during each LUW being committed at a commit point for that LUW; maintaining a log of updates made to the stored data; detecting the oldest uncommitted update made to the stored data; calculating a recovery point dependent upon the start time of the oldest uncommitted update: taking a backup copy of at least a portion of the stored data while that portion is available for update; and when necessary, recovering tile database by reinstating the backup copy to provide a working copy and applying the updates contained in any log entries made after said recovery point.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-01-09 | 1998-07-11 | 1999-01-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-01-09 | 2002-07-11 | 2003-01-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-01-09 | 2006-07-11 | 2007-01-10 | $7700.00 | Window Closed / Lapsed |