Ex Parte Bybell et al

Patent Trial and Appeal Board

Feb 27, 2017

13785212 (P.T.A.B. Feb. 27, 2017)

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APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
13/785,212 03/05/2013 Anthony J. Bybell POU920120039US2 3301
46429 7590 03/01/2017
C ANTOR mT RT TRN T T P-TRM POT TOHKFFPSTF EXAMINER
20 Church Street FA YE-JOYNER, HANNAH A
22nd Floor
Hartford, CT 06103 ART UNIT PAPER NUMBER
2139
NOTIFICATION DATE DELIVERY MODE
03/01/2017 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
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PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte ANTHONY J. BYBELL and MICHAEL K. GSCHWIND
Appeal 2016-003427
Application 13/785,212
Technology Center 2100
Before JOHN A. JEFFERY, BRADLEY W. BAUMEISTER, and
JASON M. REPKO, Administrative Patent Judges.
REPKO, Administrative Patent Judge.
DECISION ON APPEAL
STATEMENT OF THE CASE
Appellants appeal under 35 U.S.C. § 134(a) from the Examiner’s
rejection of claims 1 and 3—7. App. Br. I.1 Claim 2 has been canceled. Id.
We have jurisdiction under 35 U.S.C. § 6(b).
We reverse.
1 Throughout this opinion, we refer to (1) the Final Action (“Final Act.”)
mailed February 11, 2015, (2) the Appeal Brief (“App. Br.”) filed July 7,
2015, (3) the Examiner’s Answer (“Ans.”) mailed November 25, 2015, and
(4) the Reply Brief (“Reply Br.”) filed January 22, 2016.
Appeal 2016-003427
Application 13/785,212
THE INVENTION
Appellants’ invention determines whether a first page-table entry
(PTE) may be joined with a second PTE. Spec. 1 6. Specifically, the system
uses a page table for translating virtual addresses to main storage addresses.
Id. 1 6. The PTEs contain fields for a physical address, e.g., an address to
main storage, and a virtual address. Id. H 13, 19. The invention determines
whether two contiguous PTEs refer to contiguous main-storage pages.
Id. | 6. If so, the invention (1) joins multiple PTEs and (2) sets a marker for
the PTE to indicate that the referred-to main-storage pages are contiguous.
Id. 6, 23. Therefore, the invention allows a larger address space to be
translated for a given number of PTEs. Id. 19.
Claim 1 is reproduced below with our emphasis:
1. A computer implemented method for accessing
memory locations, the method comprising:
identifying, by a processor, a first page table entry (PTE)
of a page table for translating virtual addresses to main storage
addresses, the page table comprising a second PTE contiguous
with the first page table entry;
determining, with the processor, whether the first PTE
may be joined with the second PTE, the determining based on
the respective first page and second page of main storage being
contiguous, the determining including confirming that the first
PTE and the second PTE are valid; and
setting a respective marker in each of the first PTE and the
second PTE in the page table for indicating that the main storage
pages identified by the first PTE and the second PTE are
contiguous, wherein the first PTE and the second PTE each
comprise a respective physical address field, and wherein a first
value that is stored in the physical address field of the first PTE
is different from a second value that is stored in the physical
address field of the second PTE.
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Appeal 2016-003427
Application 13/785,212
THE REJECTIONS
The Examiner relies on the following as evidence:
Stecher US 2009/0019253 A1 Jan. 15,2009
Grisenthwaite US 2011/0225389 A1 Sept. 15, 2011
Claims 1 and 3—72 are rejected under 35 U.S.C. § 103(a) as
unpatentable over Stecher and Grisenthwaite. Final Act. 2—12
Claims 1 and 3—7 are provisionally rejected on the ground of non-
statutory obviousness-type double patenting over co-pending U.S. Patent
Application No. 13/517,738. Final Act. 13—19.
THE OBVIOUSNESS REJECTION OVER STECHER AND
GRISENTHWAITE
Contentions
The Examiner finds that Stecher discloses every recited element of
claim 1, except for the recited setting a marker in the page table.
Final Act. 2-4. The Examiner relies on Grisenthwaite to teach this feature in
concluding that claim 1 would have been obvious. Id. According to the
Examiner, Grisenthwaite uses a page table with PTEs having a physical-
address field and hint data. Id. at 4. In particular, the Examiner finds that
Grisenthwaite’s hint data corresponds to the recited marker because the hint
data indicates whether the PTEs’ physical-address fields refer to contiguous
physical-memory pages. Ans. 2—3.
2 The Final Rejection contains rejections for claim 2 under § 103 and on the
ground of non-statutory obvious-type double patenting. Final Act. 5—6, 13—
14. Appellants, however, have canceled this claim (App. Br. 1), and thus,
claim 2 is not involved in this appeal.
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Appeal 2016-003427
Application 13/785,212
Appellants argue that the Stecher-Grisenthwaite combination does not
set a respective marker in each of a first and second PTE, as recited in
claim 1. App. Br. 3^4; Reply Br. 2—3. According to Appellants,
Grisenthwaite translates contiguous virtual pages using the translation
information in PTE 44, but Grisenthwaite does not use a second PTE to
obtain a second contiguous physical address. App. Br. 3 (citing
Grisenthwaite 140). Rather, Appellants contend that Grisenthwaite saves
space by using the same information to translate a second contiguous
address. App. Br. 3; Reply Br. 2—3. So in Appellants’ view, Grisenthwaite
does not set the hint data in two consecutive PTEs containing consecutive
physical addresses. App. Br. 3; Reply Br. 2—3.
Issue
Under § 103, has the Examiner erred in rejecting claim 1 by finding
that Grisenthwaite would have taught or suggested a setting a respective
marker in each of a first and second PTE having different, contiguous
physical-address fields, as recited?
Analysis
Claim 1 recites two PTEs. Of the several claim limitations directed to
these PTEs, the following are most relevant to our inquiry. First, particular,
the PTEs must be contiguous. Second, each PTE comprises a physical-
address field. Third, the marked PTEs further have different, contiguous
physical addresses (i.e., “setting a respective marker in each of the first PTE
and the second PTE”).
Appellants argue that the Examiner erred by finding that
Grisenthwaite’s PTEs meet, at least, the third requirement above.
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Appeal 2016-003427
Application 13/785,212
App. Br. 3—\\ Reply Br. 2—3. Appellants’ argument is persuasive. Because
the Examiner relies on Grisenthwaite as teaching the limitation at issue
(Final Act. 4), we confine our discussion to Grisenthwaite.
In particular, Grisenthwaite performs a top-down page-table walk to
translate virtual-memory addresses to physical-memory addresses.
Grisenthwaite Abstract. Grisenthwaite stores translation data in a hierarchy
of tables. Id. 1 8. Translation data recovered from the walk is cached in
translation lookaside buffer (TLB) 20. Id. 139. If a memory access is made
to a virtual-address page stored in TLB 20, the system does not need to
perform another walk through the tables to recover the translation data. Id.
To further improve translation efficiency, Grisenthwaite maintains
“hint data” in the page table to indicate contiguous pages. Id. 140. That is,
hint data indicates that pages located contiguously within virtual memory are
also located contiguously in physical memory. Id. 116. Accordingly, hint
data indicates that a group of small pages could be represented by a single
virtual-to-physical address translation of a larger-sized page. Id. 116. For
example, in the Examiner-cited embodiment, virtual- and physical-memory
pages are 4 kB. Id. 139. Hint data indicates that both physical-memory and
virtual-memory pages are stored contiguously in a 64 kB block. Id. 140.
Grisenthwaite marks the translation data cached in TLB 20 to indicate that
the translation data applies to 16 contiguous 4 kB virtual pages. Id. This
strategy saves storage space in TLB 20. Id.
The Examiner finds that page tables inherently have multiple entries,
and, thus, Grisenthwaite must have more than just PTE 44 in the table.
Ans. 3. The Examiner further notes that Stecher discloses this as well. Id.
Even assuming, without deciding, that these findings are correct, claim 1
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Appeal 2016-003427
Application 13/785,212
requires more than multiple PTEs. Here, claim 1 requires that the two
contiguous PTEs are (1) marked by the setting step, and (2) have contiguous
physical addresses.
Although Grisenthwaite translates contiguous virtual pages using the
translation information in PTE 44, we agree with Appellants (App. Br. 3)
that the Examiner has not shown that Grisenthwaite marks a second PTE
with a second different physical address contiguous with PTE 44’s physical
address.
Rather, Grisenthwaite uses the same translation data for multiple
contiguous virtual pages to save space. Grisenthwaite 140. For example,
Grisenthwaite’s PTE 44 only stores the most significant 52 bits of the
physical address. Grisenthwaite 138. The system then generates the full
64-bit physical address using the least significant 12 bits of the virtual
address. Id.', see also id. Fig. 2, element 42. Accordingly, Grisenthwaite’s
Figure 2 only shows these 52 bits (“PA[63:12]”) in PTE 44, not a list of
contiguous physical addresses in the table. See id., Fig. 2. And when the
PTE 44 contains hint data 46 (the Examiner-mapped “marker”),
Grisenthwaite applies the marked translation data to 16 contiguous virtual
pages. Id. 140. So although Grisenthwaite’s hint-data 46 indicates a
correspondence between contiguous virtual addresses and contiguous
physical addresses {id.), the Examiner has not shown that Grisenthwaite
teaches or suggests storing each of those contiguous physical address in
separate PTEs along with that hint data.
Because Appellants’ arguments on this issue (App. Br. 3^4;
Reply Br. 2—3) are dispositive, we need not reach the remaining arguments.
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Appeal 2016-003427
Application 13/785,212
Accordingly, we do not sustain the rejection of independent claim 1 or
of dependent claims 3—7 for similar reasons.
THE PROVISIONAL DOUBLE-PATENTING REJECTION
Although Appellants do not provide arguments against this rejection
(see App. Br. 2—6; Reply Br. 2—3), based on the facts in this record, we
decline to reach the Examiner’s provisional rejection of claims 1 and 3—7 on
the ground of non-statutory obviousness-type double patenting. See Ex
parte Moncla, 95 USPQ2d 1884, 1885 (BPAI 2010) (precedential)
(indicating that panels have the flexibility not to reach provisional
obviousness-type double patenting rejections).
CONCLUSION
We do not sustain the Examiner’s rejection of claims 1 and 3—7 under
§103.
DECISION
We reverse the Examiner’s rejection of claims 1 and 3—7 under § 103.
REVERSED
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