X. Shen, Arvind, and L. Rudolph. Commit-Reconcile & Fences (CRF): A New Memory Model for Architects and Compiler Writers. In the 26th International Symposium On Computer Architecture, Atlanta, Georgia, May 1999. 18  Home/Search   Document Not in Database   Summary   Related Articles   Check

....how reachability analysis can be done in the Esterel environment for such complex veri cation problems. To our knowledge, this is the rst such study involving Esterel and cache coherence protocols. In this paper, we shall 1. Model CRF memory model and the various Cachet micro protocols [1, 2, 3] in Esterel, and 2. Verify properties of Cachet protocols in a graded fashion using the veri cation environment of Esterel. 2. Distributed Shared Memory Models Cache plays a vital role in controlling the latency between processor and memory access for reading and writing. In a shared memory ....

....Storel (store local) iii) Commit, iv) Reconcile and (v) Fence. Since, our goal is to study the cache coherence model, we do not consider the Fence instruction, which is related to instruction reordering. A formal detailed description of CRF using Term Rewriting Systems (TRS s) can be found in [2]. The above instructions are generated by the processors for their local cache (or sache) cells. A sache cell is a single location of a cache at a Site that contains copies of memory location when they are read by the processors. A cell contains the address of the memory location it reads and its ....

X. Shen, Arvind, and L. Rudolph. Commit-Reconcile & Fences (CRF): A New Memory Model for Architects and Compiler Writers. 26th Int. Symp. on Computer Architecture, Atlanta , 1999.

....of F 1 within i and bound the relative error of F 2 within q. The value of the third conit F 3 is the number of updates on sub object y. The numerical error of F 3 is bounded to zero, which means updates on y will incur synchronization right away. Memory Consistency Models in Multi Processors [16, 22, 27, 36] Numerous number of memory consistency models have been proposed in the context of multi processor distributed shared memory. Due to space limitations, here we cannot discuss those models individually and can only give a high level abstract discussion. Most of the consistency models are defined by ....

X. Shen, Arvind, and L. Rudolph. Commit-reconcile Fences (CRF): A New Memory Model for Architects and Compiler Writers. In Proceedings of the 26th Annual International Symposium on Computer Architecture, May 1999.

....cache consistency requirements of applications. This approach is inspired by Shen, Arvind, and Rudolph s CRF consistency model for hardware architectures, which allows the compiler to specify consistency requirements and for different run time systems to implement those requirements differently [27]. By allowing applications to specify required semantics rather than programming to the implementation details of a particular system, CRF improves code portability and also allows more opportunities for performance optimization. Both concerns are important for ad hoc distributed systems. For ....

X. Shen, Arvind, and L. Rudolph. CommitReconcile & Fences (CRF): A New Memory Model for Architects and Compiler Writers. In Proceedings of the Twenty-Sixth International Symposium on Computer Architecture, May 1999.

....performance than alternate communication architectures, such as one that relies only on cache coherent shared memory hardware. Furthermore, evaluation in this thesis focuses on the message passing aspect of StarT Voyager NES, as shared memory support is studied by other research group members [99, 98, 97]. Our evaluation of the StarT Voyager NES shows that with an appropriate architecture, multi interface support and flexible protected sharing of the NIU and network are compatible with high performance and low latency. For example, a comparison with StarT X [42] an I O bus message passing NIU ....

X. Shen, Arvind, and L. Rudolph. Commit-Reconcile & Fences (CRF): A New Memory Model for Architects and Compiler Writers. In Proceedings of the 26th International Symposium On Computer Architecture, Atlanta, May 1999.

....memory system implements a memory model, which defines the semantics of memory access instructions. An ideal memory model should allow efficient and scalable implementations while still having simple semantics for architects and compiler writers to reason about. Commit Reconcile Fences (CRF) SAR99b] is a mechanism oriented memory model intended for architects and compiler writers rather than for high level parallel programming. It is intended to give architects great flexibility for efficient implementations, while giving compiler writers adequate control. It can be used to give precise ....

....the memory with location a updated with value v. Figure 3 shows the rules in summarized form. The tabular description are easily translated into formal TRS rules (cases that are not specified represent illegal or unreachable states) The complete definition of CRF can be found elsewhere [SAR99b,She00] 1.2 The Cachet Protocol The Cachet protocol is a directory based adaptive cache coherence protocol to implement the CRF memory model in distributed shared memory systems. It is a seamless integration of several so called micro protocols (Base, Writer Push and 5 Migratory) though each ....

Xiaowei Shen, Arvind, and Larry Rudolph. Commit-Reconcile & Fences (CRF): A New Memory Model for Architects and Compiler Writers. In Proceedings of the 26th International Symposium on Computer Architecture, May 1999.

.... is the ultimate judge, we believe that our descriptions of micro architectures are more precise than what one may find in a modern textbook [4] It is the clarity of these descriptions that lets us study the impact of features such as write buffers or caches, especially in multiprocessor systems [10, 9]. In fact, part of the motivation for this work came from one of the author s experience in teaching computer architectures. 1 2 Term Rewriting Systems A term rewriting system is defined as a tuple (S, R, S 0 ) where S is a set of terms, R is a set of rewriting rules, and S 0 is a set of ....

....processor to memory buffer (pmb) the memory provides its responses via a 6 memory to processor buffer (mpb) Exactly how the memory system is organized is not discussed. However, memory system details can be added in a modular fashion without changing the processor description presented here [10, 9]. We need to add two new components, rob and btb, to the processor state. Reorder buffer rob is a complex device to model because different types of operations need to be performed on it. It can be thought of as a FIFO queue which is initially empty (ffl) We use the constructor Phi , which is ....

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Xiaowei Shen, Arvind, and Larry Rudolph. Commit-Reconcile & Fences (CRF): A New Memory Model for Architects and Compiler Writers. In Proceedings of the 26th International Symposium On Computer Architecture, Atlanta, Georgia, May 1999.

....MA 02139 arvind lcs.mit.edu Xiaowei Shen IBM T.J. Watson Research Center P.O. Box 704 Yorktown Heights, NY 10598 xwshen us.ibm.com ABSTRACT This paper describes alternative memory semantics for Java programs using an enriched version of the Commit Reconcile Fence (CRF) memory model [16]. It outlines a set of reasonable practices for safe multithreaded programming in Java. Our semantics allow a number of optimizations such as load reordering that are currently prohibited. Simple thread local algebraic rules express the effects of optimizations at the source or bytecode level. The ....

....the write operation also participates in the synchronization. For each read operation, a value set is defined as the set of legal values that can be returned. CRF is intended as a mechanism oriented memory model which exposes both data replication and instruction reordering at the ISA level [16]. It is intended for architects and compiler writers rather than for high level parallel programming. The present paper is the first formal attempt to map a high level language into the CRF model. There is a rich literature on architecture level memory models; the interested reader is referred to ....

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X. Shen, Arvind, and L. Rudolph. Commit-Reconcile & Fences (CRF): A New Memory Model for Architects and Compiler Writers. In Proceedings of the 26th International Symposium On Computer Architecture, Atlanta, Georgia, May 1999.

....Memory Model Rules chet more suitable than other protocols for scalable DSM systems. Sophisticated cache coherence protocols are notoriously difficult to get right for DSM systems, but our job is made easier by two things. First, Cachet implements the CommitReconcile Fences (CRF) memory model [10], which exposes a semantic notion of caches, and decomposes load and store instructions into finer grain operations. CRF exposes mechanisms that are needed to specify protocols precisely. It separates how a cache provides correct values from how it maintains coherence. Second, we use a design ....

....micro protocols, and Section 5 presents a seamless integration of two of the micro protocols. Finally we present our conclusions in Section 6. 2 The CRF Memory Model CRF is a mechanism oriented memory model that exposes both data replication and instruction reordering at the programming level [10]. It decomposes load and store instructions into finer grain operations that operate on a local semantic cache (sache) The model assumes that memory instructions can be reordered as long as data dependence constraints are preserved, and provides memory fences to enforce ordering if needed. There ....

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X. Shen, Arvind, and L. Rudolph. Commit-Reconcile & Fences (CRF): A New Memory Model for Architects and Compiler Writers. In Proceedings of the 26th International Symposium On Computer Architecture, Atlanta, May 1999.

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X. Shen, Arvind, and L. Rudolph. Commit-Reconcile & Fences (CRF): A New Memory Model for Architects and Compiler Writers. In the 26th International Symposium On Computer Architecture, Atlanta, Georgia, May 1999. 18

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X. Shen, Arvind, and L. Rudolph. Commit-Reconcile & Fences (CRF): A new memory model for architects and compiler writers. In Proc. ISCA, pages 150--161, 1999. 14

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X. Shen, Arvind, and L. Rudolph. Commit-Reconcile & Fences (CRF): A New Memory Model for Architects and Compiler Writers. In the 26th International Symposium On Computer Architecture, Atlanta, Georgia, May 1999. 18

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X. Shen, Arvind, and L. Rudolph. Commit-Reconcile & Fences (CRF): A new memory model for architects and compiler writers. In Proc. ISCA, pages 150--161, 1999. 9

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Shen, X., Arvind, Rudolph, L.: Commit-Reconcile & Fences (CRF): A New Memory Model for Architects and Compiler Writers. Proc. ISCA (1999) 150-161

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X. Shen, Arvind, and L. Rudolph. Commit-Reconcile & Fences (CRF): a new memory model for architects and compiler writers. In the 26th International Symposium On Computer Architecture, Atlanta, Georgia, May 1999.

No context found.

X. Shen, Arvind, and L. Rudolph. Commit-Reconcile & Fences (CRF): A New Memory Model for Architects and Compiler Writers. In the 26th International Symposium On Computer Architecture, Atlanta, Georgia, May 1999.

No context found.

X. Shen, Arvind, and L. Rudolph. Commit-Reconcile & Fences (CRF): A new memory model for architects and compiler writers. In Proc. ISCA, pages 150-161, 1999.

No context found.

Shen, X., Arvind, Rudolph, L.: Commit-Reconcile & Fences (CRF): A New Memory Model for Architects and Compiler Writers. Proc. ISCA (1999) 150-161

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