US 7,296,125 B2 · Preserving a snapshot of selected data of a mass storage system

Abstract

Maintaining logically consistent backups using minimal data transfer. A backup, or snapshot, copy of original data is created and stored. A user designates data blocks that are to be backed up in a process of creating a subsequent snapshot copy of the data. Data blocks that are to be backed up might include those associated with active files having data of interest to the user. Data blocks that are not desired for backup might include, for example, swap files, printer buffers and temp files. The changes that have been made to the data blocks that have been designated for backup are applied to the snapshot copy after a specified time period has elapsed. Since only desired data blocks are backed up to the snapshot copy, memory, processing cycles and communication bandwidth are used more efficiently than if all data blocks were to be backed up to the snapshot copy.

Drawings

Drawings are temporarily unavailable. Open the PDF at USPTO

Drawings

Claims28

Dependent claims

In a computer system having a mass storage device that stores data blocks, a method of creating a snapshot copy of selected data blocks, comprising the acts of:

designating first data blocks of the mass storage device to be included in a snapshot copy that is to preserve the designated first data blocks as the designated first data blocks existed at a first point in time;
marking second data blocks of the mass storage device as not protected so as to exclude the second data blocks from the snapshot copy;
ensuring that the designated first data blocks are in a logically consistent state such that the first point in time corresponds to a time when no activity exists on the mass storage device;
as the designated first data blocks at the mass storage device change after the first point in time, identifying specific data blocks of the designated first data blocks that change at the mass storage device;
preserving a copy of only the specific data blocks of the designated first data blocks that change and not a copy of the data blocks of the second data blocks that change, wherein the preserved copy of the changed designated data blocks represents an original copy of the changed data blocks of the designated first data blocks prior to changing;
backing up the designated first data blocks to the snapshot copy without interrupting access to the mass storage device;
and
providing access to the snapshot copy of the designated first data blocks.

5 more elements

In a computer system having a mass storage device that stores data blocks, a method of restoring data of the mass storage device using a snapshot copy of selected data blocks, comprising the acts of:

marking the data blocks such that a first subset of data blocks are marked as desirable for backup and a second subset of data blocks are marked as being undesirable for backup;
as the data blocks at the mass storage device change after a first point in time, identifying the data blocks of the first subset that change at the mass storage device;
preserving only a copy of the data blocks of the first subset that change and not a copy of the data blocks of the second subset that change, wherein the copy of the changed data blocks represents an original copy of the changed data blocks of the first subset prior to changing;
maintaining a snapshot copy of the first subset of the data blocks stored in the mass storage device, the snapshot copy preserving the first subset of the data blocks as the first subset existed at the first point in time without preserving the second subset of the data blocks that are marked as being undesirable for backup in the snapshot copy and wherein the snapshot copy is created at a time when the first subset of the data blocks is in a logically consistent state such that no activity is present on the mass storage device, wherein the snapshot copy includes:
preserved copies of those data blocks of the first subset of the data blocks that have changed at the mass storage device after the first point in time;
and
original copies of those data blocks of the first subset of the data blocks that have not changed after the first point in time;
experiencing loss of at least some of the first subset of the data blocks at the mass storage device after the first point in time;
and
restoring the first subset of the data blocks of the mass storage device using the snapshot copy.

7 more elements

In a computer system having a mass storage device that stores data blocks, a method of providing users access to a snapshot copy of selected data blocks while providing ongoing access to the data blocks stored on the mass storage device, comprising the acts of:

receiving an instruction to create a snapshot copy of selected data blocks on a mass storage device, wherein second data blocks are marked as unprotected and excluded from the instruction to create a snapshot copy;
ensuring that the selected data blocks are in a logically consistent state such that no activity is present regarding at least the selected data blocks;
as the data blocks at the mass storage device change after a first point in time, identifying the data blocks of the selected data blocks that change at the mass storage device;
preserving only a copy of the data blocks of the selected data blocks that change and not a copy of the data blocks of the second data blocks that change, wherein the copy of the changed data blocks represents an original copy of the changed data blocks of the selected data blocks prior to changing;
maintaining the snapshot copy of the selected data blocks stored in the mass storage device without interrupting access to the mass storage device, the snapshot copy preserving the selected data blocks as the selected data blocks existed at the first point in time, wherein the snapshot copy includes:
preserved copies of those data blocks of the selected data blocks that have changed at the mass storage device after the first point in time;
and
original copies of those data blocks of the selected data blocks that have not changed after the first point in time;
providing access to the snapshot copy of the selected data blocks, such that changes to the snapshot copy do not change the selected data blocks stored on the mass storage device;
and
while providing access to the snapshot copy, providing access to the selected data blocks stored on the mass storage device, such that changes to the selected data blocks stored on the mass storage device do not change the snapshot copy.

8 more elements

In a computer system having a mass storage device that stores data blocks, a method of creating multiple snapshot copies of selected data blocks, comprising:

marking a first designated subset of data blocks as protected and marking a second subset of data blocks as unprotected;
as the data blocks at the mass storage device change after a first point in time, identifying the data blocks of the first designated subset that change at the mass storage device;
preserving only a copy of the data blocks of the first designated subset that change and not a copy of the data blocks of the second subset that change, wherein the copy of the changed designated data blocks represents an original copy of the changed data blocks of the first designated subset prior to changing;
maintaining a first snapshot copy of a first designated subset of the data blocks stored in the mass storage device, the snapshot copy preserving the first designated subset of the data blocks as the first designated subset existed at the first point in time without preserving second subset of data blocks that have been marked as unprotected, wherein the first snapshot copy is created at a first time when the designated subset of data blocks is in a logically consistent state such that no activity is present in the mass storage device and wherein a particular subset of the data blocks stored in the mass storage device are not designated for backup in the snapshot copy, wherein the first snapshot copy includes:
preserved copies of those data blocks of the subset of first designated data blocks that have changed at the mass storage device after the first point in time;
and
original copies of those data blocks of the first designated subset of the data blocks that have not changed after the first point in time;
and
as the data blocks at the mass storage device change after a second point in time, identifying the data blocks of the first designated subset that change at the mass storage device;
preserving only a copy of the data blocks of the first designated subset that change and not a copy of the data blocks of the second subset that change, wherein the copy of the changed designated data blocks represents an original copy of the changed data blocks of the first designated subset after the first point in time prior to changing;
maintaining a second snapshot copy of a second designated subset of the data blocks stored in the mass storage device, the snapshot copy preserving the second designated subset of the data blocks as the designated subset existed at the second point in time without preserving the second subset of data blocks, wherein the second snapshot copy is created at a second time when the designated subset of data blocks is in a logically consistent state such that no activity is present in the mass storage device and wherein another subset of data blocks stored in the mass storage device are excluded from backup in the second snapshot copy, wherein the second snapshot copy includes:
preserved copies of those data blocks of the second designated subset of the data blocks that have changed at the mass storage device after the second point in time;
and
original copies of those data blocks of the second designated subset of the data blocks that have not changed after the second point in time;
and
continuing to provide access to the mass storage device while maintaining the first and second snapshot copy.

13 more elements

Dependencies are inferred from the claim text.

Description14,781 words

Summary1,701 words

#1. The Field of the Invention

#The present invention relates to the protection of computer data, and more particularly to a system and method for taking a snapshot copy of only certain sectors on one or more mass storage systems.

#2. Background and Related Art

Brief description of the drawings8 figures

#In order to describe the manner in which the above-recited and other advantages and features of the invention can be obtained, a more particular description of the invention briefly described above will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. Understanding that these drawings depict only typical embodiments of the invention and are not therefore to be considered to be limiting of its scope, the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings in which:

#FIG. 1 is a block diagram representing a system of the present invention;

#FIG. 2 is a diagram illustrating the timing of one method of the present invention;

Detailed description12,849 words

#The present invention extends to both systems and methods for taking a snapshot of only those data sectors that are desirable to be backed up from a mass storage means, rather than taking a snapshot of all the data in that mass storage means. Since a snapshot is taken of only the desirable data, this invention optimizes both time and storage space in providing a back up copy of data located on a mass storage means.

#The invention is described by using diagrams to illustrate either the structure or the processing of certain embodiments to implement the systems and methods of the present invention. Using the diagrams in this manner to present the invention should not be construed as limiting of its scope. The present invention can be practiced with general purpose or special purpose computers and all such computer systems should be included within its scope.

#Embodiments within the scope of the present invention also include computer-readable media having encoded therein computer-executable instructions or data structures. Such computer-readable media can be any available media that can be accessed by a general purpose or special purpose computer. By way of example, and not limitation, such computer-readable media can comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, magneto-optical storage devices, or any other medium which can be used to store the desired computer-executable instructions and data structures and which can be accessed by a general purpose or special purpose computer. Combinations of the above should also be included within the scope of computer-readable media. In turn, registers of a CPU or other processing unit that store computer-executable instructions or data structures while decoding and executing the same are also included within the scope of the computer-readable media. Computer-executable instructions comprise, for example, executable instructions and data which cause a general purpose computer or special purpose computer to perform a certain function or a group of functions.

Facts

Application

09/997,643Filed 29 Nov 2001

Published

US 2003/0101321 A129 May 2003

Granted

13 Nov 2007

Term ended

31 Dec 2023

Estimated · how

20 years from earliest known nonprovisional domestic filing plus recorded patent term adjustment, including 762 days of adjustment. Maintenance-fee lapses, terminal disclaimers and statutory extensions have not been checked. The continuity chain may be incomplete; this is not an enforceability determination.

Classification7 codes

G06F 11/1451
Management of the data involved in backup or backup restore: by selection of backup contents
G06F 2201/82
Indexing scheme relating to error detection, to error correction, and to monitoring: solving problems relating to consistency
G06F 2201/84
Indexing scheme relating to error detection, to error correction, and to monitoring: using snapshots, i.e. a logical point-in-time copy of the data
Y10S 707/99953
Coherency, e.g. same view to multiple users: recoverability

Timeline

28 Nov 2001Assigned to Legato Systems, Inc.assignment of assignor's interest
29 Nov 2001Application filedUS 09/997,643
3 Apr 2003Assigned to Legato Systems, Inc.assignment of assignor's interest
29 May 2003PublishedUS 2003/0101321 A1
24 Nov 2003Assigned to Emc Corporationmerger
13 Nov 2007GrantedUS 7,296,125 B2
21 Sep 2016Assigned to Credit Suisse AG, Cayman Islands Branch, AS Collateral Agentsecurity agreement
21 Sep 2016Assigned to The Bank of New York Mellon Trust Company, N.A., AS Notes Collateral Agentsecurity agreement
29 Sep 2016Assigned to Emc IP Holding Company LLCassignment of assignor's interest
21 Mar 2019Assigned to The Bank of New York Mellon Trust Company, N.A.security agreement
22 Apr 2020Assigned to The Bank of New York Mellon Trust Company, N.A.security agreement
3 Nov 2021Assigned to Asap Software Express, Inc., Aventail LLC, Credant Technologies, Inc., Dell USA L.P., Dell International, L.L.C., Dell Marketing L.P., Dell Products L.P., Dell Software Inc., Dell Systems Corporation, Emc Corporation, Emc IP Holding Company LLC, Force10 Networks, Inc., Maginatics LLC, Mozy, Inc., Scaleio LLC, Wyse Technology L.L.C.release of security interest
26 Apr 2022Assigned to Dell Marketing Corporation (Successor-In-Interest To Asap Software Express, Inc.), Dell Marketing L.P. (On Behalf of Itself and AS Successor-In-Interest To Credant Technologies, Inc.), Dell USA L.P., Dell International L.L.C., Dell Products L.P., Dell Marketing Corporation (Successor-In-Interest To Force10 Networks, Inc. and Wyse Technology L.L.C.), Emc Corporation (On Behalf of Itself and AS Successor-In-Interest To Maginatics LLC), Emc IP Holding Company LLC (On Behalf of Itself and AS Successor-In-Interest To Mozy, Inc.), Scaleio LLCrelease of security interest in patents previously recorded at reel/frame (040136/0001)
20 May 2022Assigned to Dell Marketing Corporation (Successor-In-Interest To Asap Software Express, Inc.), Dell Marketing L.P. (On Behalf of Itself and AS Successor-In-Interest To Credant Technologies, Inc.), Dell USA L.P., Dell International L.L.C., Dell Products L.P., Dell Marketing Corporation (Successor-In-Interest To Force10 Networks, Inc. and Wyse Technology L.L.C.), Emc Corporation (On Behalf of Itself and AS Successor-In-Interest To Maginatics LLC), Emc IP Holding Company LLC (On Behalf of Itself and AS Successor-In-Interest To Mozy, Inc.), Scaleio LLCrelease of security interest in patents previously recorded at reel/frame (045455/0001)
23 Jun 2022Assigned to Dell Marketing L.P. (On Behalf of Itself and AS Successor-In-Interest To Credant Technologies, Inc.), Dell International L.L.C., Dell Products L.P., Dell USA L.P., Emc Corporation, Dell Marketing Corporation (Successor-In-Interest To Force10 Networks, Inc. and Wyse Technology L.L.C.), Emc IP Holding Company LLCrelease of security interest in patents previously recorded at reel/frame (053546/0001)
31 Dec 2023Term endedEstimated, includes 762 days of adjustment

Preserving a snapshot of selected data of a mass storage system

Life of this patent

Preserving a snapshot of selected data of a mass storage system

Life of this patent

Life of this patent

Abstract

Drawings

Drawings

Claims28

Description14,781 words

Drawings

Classification7 codes

Life of this patent

Description14,781 words