Ex Parte Sampathkumar

Patent Trial and Appeal Board

Dec 27, 2016

13755567 (P.T.A.B. Dec. 27, 2016)

United States Patent and Trademark Office
UNITED STATES DEPARTMENT OF COMMERCE
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APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
13/755,567 01/31/2013 Kishore K. Sampathkumar 12-3365 9090
57299 7590
Kathy Manke
Avago Technologies Limited
4380 Ziegler Road
Fort Collins, CO 80525
12/29/2016 EXAMINER
WARREN, TRACY A
ART UNIT PAPER NUMBER
2131
NOTIFICATION DATE DELIVERY MODE
12/29/2016 ELECTRONIC
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address(es):
kathy .manke @ broadcom. com
patent.info@broadcom.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte KISHORE K. SAMPATHKUMAR
Appeal 2016-000697
Application 13/755,5671
Technology Center 2100
Before ST. JOHN COURTENAY III, MATTHEW J. McNEILL, and
SCOTT E. BAIN, Administrative Patent Judges.
McNEILL, Administrative Patent Judge.
DECISION ON APPEAL
Appellant appeals under 35 U.S.C. § 134(a) from the Examiner’s
rejection of claims 1-20, which are all the claims pending in this application.
We have jurisdiction under 35 U.S.C. § 6(b).
We affirm.
1 According to Appellant, the real party in interest is LSI Corporation. Br. 3.
Appeal 2016-000697
Application 13/755,567
STATEMENT OF THE CASE
Introduction
Appellant’s application relates to Copy-On-Write (COW) snapshots
of a RAID storage system. Abstract. Claim 1 is illustrative of the subject
matter on appeal and reads as follows:
1. A backup system for a Redundant Array of Independent
Disks (RAID) storage system, the backup system comprising:
a backup storage device that includes Copy-On-Write
snapshots of a RAID logical volume that implements a file
system; and
a backup controller operable to determine that a write
operation is pending for an extent of the logical volume, to
access allocation data for the file system to determine whether
the extent was allocated to a file of the file system when a
Copy-On-Write snapshot was created, and to copy the extent to
the snapshot responsive to determining that the extent was
allocated to a file of the file system when the snapshot was
created,
wherein the backup controller is further operable to
determine that the extent was allocated to a file of the file
system when multiple Copy-On-Write snapshots were created,
to select one of the multiple snapshots, and to copy the extent to
the selected snapshot.
The Examiner’s Rejections
Claims 1-4, 6-11, 13-18, and 20 stand rejected under 35 U.S.C.
§ 103(a) as unpatentable over Ohad Rodeh et al., IBM Research Report,
BTRFS: The Linux B-tree Filesystem, RJ10501 (ALM1207-004), July 9,
2012 (“Rodeh”) and Adkins (US 2005/0182797 Al; Aug. 18, 2005). Final
Act. 2-15.
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Application 13/755,567
Claims 5, 12, and 19 stand rejected under 35 U.S.C. § 103(a) as
unpatentable over Rodeh, Adkins, and Sailesh Chutani et al., The Episode
File System, USENIX —Winter ’92 (“Chutani”). Final Act. 15-21.
ANALYSIS
We have reviewed the Examiner’s rejections in light of Appellant’s
contentions that the Examiner has erred. We disagree with Appellant’s
contentions. Except as noted below, we adopt as our own: (1) the findings
and reasons set forth by the Examiner in the action from which this appeal is
taken and (2) the reasons set forth by the Examiner in the Examiner’s
Answer in response to Appellant’s Appeal Brief. We concur with the
conclusions reached by the Examiner. We highlight the following additional
points.
Claim 1
Appellant argues the Examiner erred in rejecting claim 1 because the
combination of Rodeh and Adkins does not teach or suggest “a backup
controller operable to . . . determine that the extent was allocated to a file of
the file system when multiple Copy-On-Write snapshots were created, to
select one of the multiple snapshots, and to copy the extent to the selected
snapshot.” Br. 7-12.
In particular, Appellant argues Rodeh does not teach creating defined
snapshots of a volume or selecting a volume snapshot to receive write data.
Br. 8. Appellant argues Rodeh also does not determine whether a node
being duplicated was previously allocated at a point in time because there is
no reason to do so without multiple snapshots. Br. 9.
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Application 13/755,567
Appellant argues Adkins does not teach or suggest multiple snapshots.
Br. 11-12. Appellant argues Adkins’s “before-images” do not have any
allocation information that indicates whether or not they were allocated
when specific COW snapshots were created. Id.
Appellant has not persuaded us of Examiner error. The Examiner
finds, and we agree, both Rodeh (Rodeh 2) and Adkins (Adkins 140) teach
creating multiple COW snapshots. Ans. 31. The Examiner further finds,
and we agree, Rodeh teaches an extent allocation tree that tracks the
allocations of these snapshots to maintain file continuity. Id. Adkins also
teaches storing snapshot metadata for multiple snapshots, which allows for
preservation of data integrity within the snapshots. See, e.g., Adkins 140.
Appellant did not file a Reply Brief and has not identified persuasive
evidence in the record to contradict the Examiner’s findings.
Accordingly, we are not persuaded the Examiner erred in rejecting
claim 1. We, therefore, sustain the rejection of claim 1. Appellant argues
the patentability of independent claims 8 and 15 for the same reasons as
claim 1. Br. 12-13. We, therefore, also sustain the rejections of claims 8
and 15 for the same reasons. We also sustain the rejections of dependent
claims 3, 6, 7, 10, 13, 14, 17, and 20, which were not argued separately from
their respective independent claims. See Br. 6-15.
Claim 2
Claim 2 recites “[t]he system of claim 1 wherein: the backup
controller is further operable to identify a Copy-On-Write snapshot for
deletion, to determine that the snapshot for deletion includes data referenced
by another Copy-On-Write snapshot, and to move the data to the other
snapshot.”
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Application 13/755,567
Appellant argues the Examiner erred in rejecting claim 2 because
Rodeh teaches shrinking a file system by copying extents, but “does not
discuss distinguishing Copy-on-Write nodes from other nodes within the
tree, so it does not explain any technique whereby if a Copy-on-Write
snapshot is about to be deleted, it may determine whether the data in that
Copy-on-Write snapshot is referenced by another Copy-on-Write snapshot.”
Br. 13.
We disagree. The Examiner finds, and we agree, Rodeh teaches
shrinking a file system (e.g., deleting snapshots) while maintaining sharing
between references that point to the data to be deleted. Ans. 32 (citing
Rodeh pp. 2, 22-25). Rodeh’s relocator moves the data to a new location to
maintain these references. Id. Appellant argues Rodeh fails to teach
specifically maintaining sharing between COW snapshots, but Appellant has
failed to persuasively explain how Rodeh’s teachings that apply to all stored
data would not apply to saved COW snapshots.
Accordingly, we are not persuaded the Examiner erred in rejecting
claim 2. We, therefore, sustain the rejection of claim 2. Appellant argues
the patentability of claims 9 and 16 for the same reasons as claim 2. Br. 13.
We, therefore, also sustain the rejections of claims 9 and 16 for the same
reasons.
Claim 4
Claim 4 recites “[t]he system of claim 1 wherein: the file allocation
data describes, for each Copy-On-Write snapshot, which extents of the
snapshot corresponded to allocated files at the time the snapshot was taken.”
Appellant argues the Examiner erred in rejecting claim 4 because
Rodeh teaches an extent allocation tree that indicates whether an extent is
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Application 13/755,567
presently allocated, not whether an extent of a snapshot corresponded with
allocated files at the point in time the snapshot was taken. Br. 13-14.
Appellant has not persuaded us of Examiner error. The Examiner
finds, and we agree, Rodeh teaches an extent allocation tree that tracks
allocated extents and back references to an extent. Ans. 32 (citing Rodeh
pp. 12-13). Adkins further teaches saving snapshot metadata for multiple
snapshots (e.g., Adkins 140) and saving data necessary to determine
whether an extent was in use when a snapshot was created (e.g., Adkins Fig.
9A). Appellant has not identified persuasive evidence in the record to
contradict the Examiner’s findings.
Accordingly, we are not persuaded the Examiner erred in rejecting
claim 4. We, therefore, sustain the rejection of claim 4. Appellant argues
the patentability of claims 11 and 18 for the same reasons as claim 4. Br. 14.
We, therefore, also sustain the rejections of claims 11 and 18 for the same
reasons.
Claim 5
Claim 5 recites “[t]he system of claim 1 wherein: the backup
controller is further operable to generate Copy-On-Write snapshots for the
logical volume, and to create allocation data for generated snapshots by
accessing file system space allocation bitmaps generated by an operating
system that implements the file system.”
Appellant argues the Examiner erred in rejecting claim 5 because
Chutani does not teach using allocation bitmaps as part of a COW system or
creating allocation data on a snapshot-by-snapshot basis from such bitmaps.
Br. 14.
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We disagree. The Examiner finds, and we agree, Chutani teaches
using allocation bitmaps as part of a COW system. Ans. 33 (citing Chutani
p. 46,17). The Examiner further finds, and we agree, Chutani teaches using
the bitmap containers to store metadata, including the allocation bitmap, in
the file system. Ans. 33. Appellant has not identified persuasive evidence
in the record to contradict the Examiner’s findings.
Accordingly, we are not persuaded the Examiner erred in rejecting
claim 5. We, therefore, sustain the rejection of claim 5. Appellant argues
the patentability of claims 12 and 19 for the same reasons as claim 5. Br. 15.
We, therefore, also sustain the rejections of claims 12 and 19 for the same
reasons.
DECISION
We affirm the decision of the Examiner rejecting claims 1-20.
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a)(1). See 37 C.F.R.
§ 1.136(a)(l)(iv).
AFFIRMED
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