Ex Parte Guthrie et al

Patent Trial and Appeal BoardNov 19, 2012

11539694 (P.T.A.B. Nov. 19, 2012)

UNITED STATES PATENT AND TRADEMARK OFFICE ____________________ BEFORE THE PATENT TRIAL AND APPEAL BOARD ____________________ Ex parte GUY L. GUTHRIE, WILLIAM J. STARKE, DEREK E. WILLIAMS, and PHILLIP G. WILLIAMS ____________________ Appeal 2010-006900 Application 11/539,694 Technology Center 2100 ____________________ Before ALLEN R. MacDONALD, DEBRA K. STEPHENS, and JUSTIN BUSCH, Administrative Patent Judges. STEPHENS, Administrative Patent Judge. DECISION ON APPEAL Appeal 2010-006900 Application 11/539,694 2 Appellants appeal under 35 U.S.C. § 134(a) (2002) from a final rejection of claims 1-17. We have jurisdiction under 35 U.S.C. § 6(b). We REVERSE. Introduction According to Appellants, the invention relates to a multi-processor data processing system and more particularly, to improved coherency management of a hierarchical cache system within a multi-processor data processing system. (Spec. 1, [0002]). STATEMENT OF THE CASE Exemplary Claim Claim 1 is an exemplary claim and is reproduced below: 1. A method of data processing in a multiprocessor data processing system including at least first and second coherency domains, wherein the first coherency domain includes at least one processing unit, a system memory and a cache memory, the method comprising: buffering a cache line in a data array of the cache memory; and setting a state field in a cache directory of the cache memory to a coherency state to indicate that: the cache line is valid in the data array, the cache line is held in the cache memory non- exclusively and is unmodified with respect to a corresponding memory block in the system memory, another cache in said second coherency domain may hold a copy of the cache line, and Appeal 2010-006900 Application 11/539,694 3 a domain indicator in the first coherency domain, which has a first state indicative of a first scope of coherency communication for the cache line that excludes the second coherency domain and a second state indicative of a second scope of coherency communication for the cache line that includes the second coherency domain, will have to be updated to the second state. References Guthrie US 2006/0224833 A1 Oct. 5, 2006 Ghai US 2006/0179242 A1 Aug. 10, 2006 Rejections (1) Claims 1-3, 6-9, 11-14, and 17 stand rejected under 35 U.S.C. § 102(e) as being anticipated by Guthrie. (2) Claims 4, 5, 10, 15, and 16 stand rejected under 35 U.S.C. § 103(a) as being unpatentable over Guthrie and Ghai. 1 ISSUE 1 35 U.S.C. § 102(e): claims 1-3, 6-9, 11-14, and 17 Appellants argue their invention is not anticipated by Guthrie (App. Br. 8-10). Specifically, Appellants contend Guthrie does not disclose setting a state field in a cache directory to a coherency state indicating the combination of four properties, as recited in claim 1 (App. Br. 9). 1 The Examiner entered a new ground of rejection for claims 5 and 16 under 35 U.S.C. § 103(a) as being unpatentable over Guthrie and Ghai, based on their dependence on claims 4 and 15, respectively (Ans. 15). Appeal 2010-006900 Application 11/539,694 4 According to Appellants, only the Shared state of Guthrie indicates “the cache line is held in the cache memory non-exclusively and is unmodified” (id.). Appellants argue the conventional Shared state, or S or Sr coherence state of Guthrie does not disclose the recited “domain indicator” and thus, Guthrie does not disclose setting a state field in a cache directory to indicate that a domain indicator in the first coherency domain will have to be updated to the second state (App. Br. 9; Reply Br. 3). Issue 1: Has the Examiner erred in finding Guthrie discloses “setting a state field in a cache directory . . . to indicate that . . . a domain indicator in the first coherency domain…will have to be updated to the second state,” as recited in claim 1? ANALYSIS We agree with Appellants that the Examiner has not shown, nor do we readily find, that the state field is set to indicate that a domain indicator will have to be updated to the second state (Reply Br. 2-3). Accordingly, the Examiner erred in finding Guthrie discloses the invention as recited in independent claim 1and commensurately recited independent claims 7 and 12. Dependent claims 2, 3, 6, 8, 9, 11, 13, 14, and 17, therefore stand with their respective independent claims. Therefore, the Examiner erred in rejecting claims 1-3, 6-9, 11-14, and 17 under 35 U.S.C. § 102(e) for anticipation by Guthrie. Appeal 2010-006900 Application 11/539,694 5 ISSUE 2 35 U.S.C. § 103(a): claims 4, 5, 10, 15, and 16 The Examiner has not shown Ghai cures the deficiencies of Guthrie. Accordingly, the Examiner erred in finding the combination of Guthrie and Ghai teaches or suggests the invention as recited in claims 4, 5, 10, 15, and 16. Therefore, the Examiner erred in rejecting claims 4, 5, 10, 15, and 16 under 35 U.S.C. § 103(a) for obviousness over Guthrie and Ghai.2 DECISION The Examiner’s rejection of claims 1-3, 6-9, 11-14, and 17 under 35 U.S.C. § 102(e) as being anticipated by Guthrie is reversed. The Examiner’s rejection of claims 4, 5, 10, 15, and 16 under 35 U.S.C. § 103(a) as being unpatentable over Guthrie and Ghai is reversed. REVERSED msc 2 We do not address the arguments regarding whether the rejection under 35 U.S.C. §103(a) is proper as we have reversed the Examiner’s rejection of their respective independent claims (see App. Br. 12 and Ans. 15).