Ex Parte Delapedraja

Patent Trial and Appeal BoardSep 18, 2012

11021253 (P.T.A.B. Sep. 18, 2012)

UNITED STATES PATENT AND TRADEMARK OFFICE ____________________ BEFORE THE PATENT TRIAL AND APPEAL BOARD ____________________ Ex parte JAROSLAV DELAPEDRAJA ____________________ Appeal 2010-004115 Application 11/021,253 Technology Center 2100 ____________________ Before DENISE M. POTHIER, BRUCE R. WINSOR, and JENNIFER S. BISK, Administrative Patent Judges. BISK, Administrative Patent Judge. DECISION ON APPEAL SUMMARY This is an appeal under 35 U.S.C. § 134(a) from the Examiner’s rejection of claims 1-34, which are all the claims pending in this application. We have jurisdiction under 35 U.S.C. § 6(b). We affirm. The Invention Appellant’s invention relates to providing efficient access to a data structure that has an ordered arrangement of elements and is shared by Appeal 2010-004115 Application 11/021,253 2 multiple tasks in a computing environment. Abstract. The claims describe associating a spinlock with the data structure. To read the data structure, each task uses a traversal iterator to point to the element in the data structure being read. The referenced element also points back to the applicable traversal iterator. While the reader task is using the pointer of its associated traversal iterator it holds the spinlock. To delete an element in the data structure, a writer task holds the spinlock and modifies the pointer of each traversal iterator that is pointed to by that element. See App. Br. 42-50, Claims App’x. Claim 1, reproduced below with emphasis added, is illustrative of the claimed subject matter. 1. A method for providing efficient access to a data structure having an ordered arrangement of elements by multiple tasks in a computing environment, comprising: associating a spinlock with the data structure; defining a plurality of traversal iterators, each having a read pointer pointing to an element within the data structure, wherein each traversal iterator is associated with a reader task to enable the plurality of traversal iterators to share access to the data structure concurrently; traversing the data structure using the reader task, wherein the reader task holds the spinlock while using the read pointer of the reader tasks’s associated traversal iterator; and deleting a selected element from the data structure using a writer task, wherein the writer task holds the spinlock while modifying the read pointer of each traversal iterators associated with the reader task whose read pointers point to the selected element being deleted. Appeal 2010-004115 Application 11/021,253 3 The Rejections 1. Claims 1-12, 27, 31, and 33 stand rejected under § 103(a) as obvious over Schimmel (US 6,601,120 B1; July 29, 2003), Kirkman (US 6,581,063 B1; June 17, 2003), and Nitta (US 5,287,521; Feb. 15, 1994). Ans. 3-14. 2. Claims 13-26, 28-30, 32, and 34 stand rejected under § 103(a) as obvious over Schimmel, Kirkman, Nitta, and Cavanaugh (US 6,016,489; Jan. 18, 2000). Ans. 15-28. THE OBVIOUSNESS REJECTION OF CLAIMS 1-12, 27, 31, AND 33 The Examiner rejected claims 1-12, 27, 31, and 33 under § 103(a) as obvious over the combination of Schimmel, Kirkman, and Nitta finding that: (1) Schimmel teaches “associating a spinlock with a data structure” and reader and writer tasks, which hold that spinlock when accessing the data structure (the “associating limitation”); (2) Kirkman teaches a plurality of traversal iterators; and (3) Nitta teaches enabling the plurality of pointers from read and write processes to share access to the data structure concurrently. Ans. 3-4. Appellant argues that none of the cited references teach or suggest “deleting a selected element from the data structure using a writer task, wherein the writer task holds the spinlock while modifying the read pointer of each traversal iterators” (the “deleting limitation”). App. Br. 27-34. Appellant also argues that the Examiner improperly combined Schimmel and Kirkman. Ans. 30-32. Appeal 2010-004115 Application 11/021,253 4 Issues 1. Under § 103, has the Examiner erred in rejecting claims 1-12, 27, 31, and 33 by finding that Schimmel, Kirkman, and Nitta collectively would have taught or suggested the deleting limitation? 2. Is the Examiner’s reason to combine the teachings of these references supported by articulated reasoning with some rational underpinning to justify the Examiner’s obviousness conclusion? Analysis We are not persuaded by Appellant’s arguments. Appellant argues that Schimmel does not disclose a plurality of traversal iterators or modifying the read pointer of each traversal iterator. App. Br 28-29. This argument is not consistent with the Examiner’s rejection which cites to Kirkman, not Schimmel, as teaching this limitation. Ans. 4, 29-30. Similarly, Appellant’s argument that Nitta does not teach the deleting limitation does not relate to the rejection because the Examiner only relied on Nitta for teaching a plurality of processes sharing access to the data structure concurrently. App. Br. 32-33; Ans. 4, 34. Appellant also argues that Kirkman does not make up for the deficiencies in Schimmel because Kirkman’s iterators do not function in the recited manner. App. Br. 29. Kirkman describes a linked list with an associated data structure used by tasks to update the linked list. See Kirkman, Abstract. The data structure is used to block subsets of the linked list from being altered by other tasks and includes “inspector objects,” which traverse the linked list without changing it (similar to a read task) and “mutator objects,” which alter the list (similar to a write task). See id. Appeal 2010-004115 Application 11/021,253 5 Mutators have associated blocker objects to block access to selected list elements while they are being altered. Id. Access is blocked by altering inspector object pointers to point to the blocker object instead of the linked list element. Id. The blocker object in turn points to a section of the linked list that is not blocked. Id. This way, an iterator object by-passes the blocked portion of the linked list. Id. The Examiner reasonably finds that the pointers associated of Kirkman’s inspector object are necessarily modified to point to the next available element on the list to prevent a “dangling pointer”—something that would have been well known to a person of ordinary skill in the art. Ans. 30. Appellant disputes this finding, stating that Kirkman only explicitly describes changing the blocking object, but does not explicitly describe modifying the inspector object pointers. App. Br. 29-30. This argument is not effective to rebut the Examiner’s finding. Appellant does not provide persuasive argument or evidence that a person of skill in the art would not know that the pointers of the inspector object are necessarily modified in order to prevent dangling pointers. Mere arguments unsupported by factual evidence are entitled to little probative value. Cf., In re Geisler, 116 F.3d 1465, 1470 (Fed. Cir. 1997). We are also not persuaded that the Examiner improperly combined Schimmel and Kirkman. Appellant argues that modification of Schimmel is not necessary because of its stated assumption that tasks that write to the data structure are rare. App. Br. 31 (citing Schimmel col. 3, ll. 27-29). This argument does not address the relevant inquiry—whether the claimed subject matter would have been obvious to those of ordinary skill in the art in light of the combined teachings of the references. See In re Keller, 642 Appeal 2010-004115 Application 11/021,253 6 F.2d 413, 425 (CCPA 1981). The Examiner’s findings regarding what Schimmel would teach a person of ordinary skill in the art are reasonable. Ans. 4-6; 10-14; see In re Mouttet, 686 F.3d 1322, 1331 (Fed. Cir. 2012) (“A reference may be read for all that it teaches, including uses beyond its primary purpose.”). Appellant also argues that a person of ordinary skill would not have looked to the teachings of Kirkman, because Kirkman’s invention eliminates the needs for locks and states that locks have the potential to affect performance. App. Br. 31 (citing Kirkman col. 2, ll. 32-45). The Examiner, however, finds that a person of ordinary skill would have realized that a spin lock was efficient and would look to Kirkman for a general solution of updating shared data structures in a lock environment. Ans. 32-33. Moreover, the Examiner explains that a person of ordinary skill in the art would have been motivated to combine the teachings of Schimmel and Kirkman “to update . . . linked lists in a multiprocessor environment which is less disruptive of tasks executing in other processors.” Ans. 4 (citing Kirkman col. 2, ll. 45-49). Appellant provides no persuasive evidence to rebut these findings. For these reasons, we conclude that Appellant has not rebutted the Examiner’s prima facie case of obviousness for representative claim 1 or claims 2, 3, 6-12, 27, 31, and 33, which were not argued separately. App. Br. 33-34. Appellant argues that claims 4 and 5 are patentable for the additional reason that the cited references fail to teach “releasing the spinlock held by the reader task immediately after” (a) each element is visited by the reader task as recited in claim 4 or (b) removing the selected element as recited in Appeal 2010-004115 Application 11/021,253 7 claim 5. App. Br. 34-36. Appellant’s sole argument is that Nitta does not disclose releasing the lock immediately after each element is visited because it requires a “shared mode counter,” as found by the Examiner. App. Br. 34. Appellant asserts that this “shared mode counter” would not be necessary if the lock was released by a reader task. App. Br. 34-36. We are not persuaded by this argument. The Examiner explains that Nitta teaches that the unlock program can be called by a task at any time. Ans. 35 (citing Nitta col. 6, ll. 15-25). This necessarily includes unlocking immediately after a read. See Ans. 35. Thus, although not explicitly stated in Nitta, Nitta does teach unlocking (releasing the spinlock) immediately after an element is visited by a reader task. “A person of ordinary skill is also a person of ordinary creativity, not an automaton.” KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 421 (2007). And a reference may be read for all that it teaches, including uses beyond its primary purpose. Mouttet, 686 F.3d at 1331. Appellant’s argument that a person of ordinary skill would not realize this because it is not explicitly stated in the reference, made without reference to persuasive supporting evidence, is not convincing. Thus, we also sustain the Examiner’s rejections of claims 4 and 5. THE OBVIOUSNESS REJECTION OF CLAIMS 13-26, 28-30, 32, and 34 The Examiner rejected claims 13-26, 28-30, 32, and 34 under § 103(a) as obvious over the combination of Schimmel, Kirkman, Nitta, and Cavanaugh. The Examiner uses the same reasoning as in the previously discussed rejection, adding that Cavanaugh teaches that the referenced element points back to the traversal iterator. Ans. 16. Appeal 2010-004115 Application 11/021,253 8 Appellant argues that Cavanaugh does not overcome the deficiencies of Schimmel, Kirkman, and Nitta argued in the previous rejection. App. Br. 36-38. Appellant adds that the Examiner improperly combined Cavanaugh with the other references. App. Br. 38-39. Issue Is the Examiner’s reason to combine the teachings of these references supported by articulated reasoning with some rational underpinning to justify the Examiner’s obviousness conclusion? Analysis We are not persuaded by Appellant’s arguments. First, as discussed above, we do not agree that Schimmel, Kirkman, and Nitta are deficient. Second, we are not persuaded by Appellant’s argument that Cavanaugh’s iterators cannot be combined with the iterators of Schimmel, Kirkman, and Nitta because of the way they are implemented. App. Br. 38-39. The relevant inquiry is whether the claimed subject matter would have been obvious to those of ordinary skill in the art in light of the combined teachings of the references. See Keller, 642 F.2d at 425. “Combining the teachings of references does not involve an ability to combine their specific structures.” In re Nievelt, 482 F.2d 965, 968 (CCPA 1973). Appellant does not provide persuasive argument or evidence that combining the various types of iterators from the references would be “uniquely challenging or difficult for one of ordinary skill in the art” at the time of Appellant’s invention. Leapfrog Enters., Inc. v. Fisher-Price, Inc., 485 F.3d 1157, 1162 (Fed. Cir. 2007) (citing KSR, 550 U.S. at 418). Finally, Appellant asserts Appeal 2010-004115 Application 11/021,253 9 that the Examiner did not provide a reason for the combination of Nitta and Cavanaugh. App. Br. 38. To the contrary, the Examiner states that it would have been obvious to combine the teachings of Nitta with Schimmel and Cavanaugh “in order to improve overall processing capability and upgrade the concurrent processing level.” Ans. 37 (citing Nitta col. 3, ll. 30-35). Appellant argues that claims 14 and 17 are patentable for the additional reason that the cited references fail to teach the additional limitations recited by these dependent claims. App. Br. 34-36. Appellant’s sole argument is identical to that advanced for claims 4 and 5—Nitta does not disclose releasing the lock immediately after each element is visited because it requires a “shared mode counter,” as found by the Examiner. As discussed above, we are not persuaded by this argument. For these reasons, we sustain the rejection of claims 13-26, 28-30, 32, and 34. DECISION The Examiner’s decision rejecting claims 1-34 is affirmed. 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)(iv). AFFIRMED babc