Raynal M. and Schiper A., A Suite of Formal Definitions for Consistency Criteria in Distributed Shared Memories. Proc. 9th Int. IEEE Conference on Parallel and Distributed Computing Systems (PDCS'96), pp. 125-131, 1996.  Home/Search   Document Details and Download   Summary   Related Articles   Check

....the local one. To allow concurrent access to the same memory location (especially for reading) the fragment comprising it can be replicated on distinct hosts. It is necessary, however, to synchronize the write access to prevent replicas from being inconsistent. 3. COHERENCE PROTOCOLS Following [7]] we assume that the DSM system is a finite set of sequential processes P 1 , P 2 , P n that can read or write a finite set X of shared locations. Each process has its own replica of the whole set X. A task for a coherence protocol is to maintain the consistent state of the replicas. A write ....

M. Raynal, and A. Schiper, A Suite of Formal Definitions for Consistency Criteria in Distributed Shard Memories, Technical Report PI n 968, IRISA Rennes, November 1995.

.... allows ample generality at the user level, however at the expense of efficiency [10] Even so, various other consistency models have appeared in the wake of sequential consistency, and many of them retain the notion of sequential consistency, albeit in a considerably restricted manner (e.g. [3, 18, 1, 2, 9]) In all of these consistency models, and after a fashion in some others as well [6, 7] one of the key concepts is that of the legality of a sequence of operations on shared objects. Starting from the specification of what the valid sequences of operations on each shared object are, a given ....

....of a legal sequence of operations that extends, in a sense to be made precise further in this section and more generally in Section 6, the partially ordered set we define to be legal. We also note that requiring this semantic equivalence is what makes our and previous related approaches (e.g. [18, 15]) totally distinct. Our first definition of legality over a partially ordered set is based on the simplifying assumption that, for every read in an execution, there exists exactly one write that appears along with it in a mi Gamma pair. Note that this does not preclude the existence of ....

[Article contains additional citation context not shown here]

M. Raynal and A. Schiper. A suite of formal definitions for consistency criteria in shared memories. In Proc. of the ISCA Int. Conf. on Parallel and Distributed Computing Systems (ICPDS'96), pages 125--130, September 1996. 14

....classify reliable and robust DSM systems. First, the design of the DSM is influenced by the coherence protocol and consistency model. It is important to consider whether these semantics are maintained when the system fails. Possible semantics are: sequential consistency[33] processor consistency[42], eager or lazy release consistency[49] entry consistency, or no consistency whatsoever. Second, some DSM systems require their user applications to be re written and or recompiled before they can take advantage of reliability. For example, if an application provides the DSM system with ....

M. Raynal and A. Schiper. A suite of formal definitions for consistency criteria in distributed shared memories. Technical report, (IRISA) Institut De Recherche En Informatique Et Syst'emes Al'eatoires, November 1995.

....atomic consistency [23] Before defining dynamic atomic consistency, we must define the global time function (gt) Function gt: The function gt(x) returns the value of a global clock when the event x occurs. Our formal definition of dynamic atomic consistency is derived from the definition in [29]: Definition 2. Dynamic Atomic Consistency: A history H is dynamic atomically consistent if there is a legal linear sequence of that respects the order AT which is defined as follows: i) o 1 , o 2 : if o 1 po o 2 then o 1 AT o 2 and ii) o 1 , o 2 : if gt(perform(o 1 ) ....

....The aim of her work, however, was to define relaxed models in terms of sequential consistency. The central hypothesis of this study is that all parallel programmers would prefer to reason as if they were programming a time sharing uniprocessor. A set of formal definitions was also proposed in [29]. The objective of this study was to understand memory models and compare them. The following memory models were defined using the proposed notation: atomic consistency, sequential consistency, causal consistency and PRAM consistency. Kohli et al. 19] also proposed a formal framework to relate ....

[Article contains additional citation context not shown here]

M. Raynal and A. Schiper, "A Suite of Formal Definitions for Consistency Criteria in Distributed Shared Memories", Technical Report PI-968, IRISA, France, 1995.

....W (x)1 p1 a. Algorithme du P lerin P2 P1 P3 Acq W (x)1 p1 p1 Rel Acq Rel Acq b. Coh rence de lib ration p1 W (x)2 W (x)2 Figure 5: Histoire du P elerin et histoire en mod ele de lib eration Diff erents mod eles de coh erence ainsi que des protocoles les impl ementant ont et e d efinis dans [Ray96] nous etudions dans ce paragraphe le mod ele de coh erence impl ement e par le protocole du P elerin. Dans les travaux de Lelann [Lel77] le jeton permet de g erer un partage de ressources et plus particuli erement une exclusion mutuelle sur cette ressource. Dans l algorithme du P elerin, ....

M. Raynal and A. Shiper. A Suite of Formal Definitions for Consistency Criteria in Distributed Shared Memories. ISCA Proceedings of the International Conference PDCS, Dijon France, pages 125--130, September 1996.

....when a new member connects with the cooperative system it has to recover the data context which is replicated. But there is a problem: consistency management between the different copies. From the most rigorous consistency model, called strict consistency, to the weakest one [Aha92, Mos93, Ray96] a co operative model must be as consistent as possible but not slow down the system with too many controlled message exchanges. In a first CAliF version we implemented a consistency protocol based on the invalidation method [Li 89] every node has an object list and for each object there is a ....

....and remains true following events which modify the system. Therefore with the Pilgrim protocol an object always has an owner or has one after finite time t. 5 Comparison between Pilgrim Implemented Consistency and Release Consistency Several consistency models and protocols have been defined in [Ray96] We will now discuss the consistency model implemented by Pilgrim protocol. In [Lel77] the token allows resource sharing and especially mutual exclusion on these W (x)3 p1 R (x)3 p2 p2 W (y)4 p2 W (y)5 p3 p3 R (x)3 R (y)5 W (x)3 p1 p3 p3 R (x)3 R (y)5 R (x)3 p2 W (y)4 p2 p2 W (y)5 a. ....

M. Raynal and A. Shiper. A Suite of Formal Definitions for Consistency Criteria in Distributed Shared Memories. ISCA Proceedings of the International Conference PDCS, Dijon France, pages 125--130, September 1996.

....These two models, verified using a maximum search depth = 1000, was found errorless. Therefore, we could think that our protocol was validated by SPIN. 5 Comparison between Pilgrim Implemented Consistency and Release Consistency Several consistency models and protocols have been defined in [13]. We will now discuss the consistency model implemented by Pilgrim protocol. In the Pilgrim algorithm, entry into the critical section occurs when the token arrives on the processor, and exit from the critical section occurs when the token leaves the processor. Release consistency which is a ....

M. Raynal and A. Shiper. A Suite of Formal Definitions for Consistency Criteria in Distributed Shared Memories. ISCA Proceedings of the International Conference PDCS, Dijon France, pages 125--130, September 1996.

No context found.

Raynal M. and Schiper A., A Suite of Formal Definitions for Consistency Criteria in Distributed Shared Memories. Proc. 9th Int. IEEE Conference on Parallel and Distributed Computing Systems (PDCS'96), pp. 125-131, 1996.

No context found.

Raynal M. and Schiper A., A Suite of Formal Definitions for Consistency Criteria in Distributed Shared Memories. Proc. 9th Int. IEEE Conference on Parallel and Distributed Computing Systems (PDCS'96), pp. 125-131, 1996.

....5 main sections. Section 2 presents the basic shared memory model. Then, Sections 3, 4, 5, and 6 give formal definitions for sequential, atomic, causal and PRAM consistency, respectively. Basic principles of protocols implementing these criteria are also given. The interested reader will consult [18] that offers an in depth study of the topic addressed in this paper. 2 Shared Memory Model 2.1 Notations A shared memory system is composed of a finite set of sequential processes P 1 ; Pn that interact via a finite set X of shared objects. Each object x 2 X can be accessed by read and ....

M. Raynal and A. Schiper. A Suite of Formal Definitions for Consistency Criteria in Distributed Shared Memories. Irisa Research Report 968, 27 pages, Dec. 1995.

No context found.

M. Raynal and A. Shiper. A Suite of Formal Definitions for Consistency Criteria in Distributed Shared Memories. ISCA Proceedings of the International Conference PDCS, Dijon France, pages 125--130, September 1996.

No context found.

M. Raynal and A. Schiper. A suite of formal definitions for consistency criteria in distributed shared memories. In Proceedings Int Conf on Parallel and Distributed Computing (PDCS'96), pages 125--130, Dijon, France, September 1996. ISCA.

No context found.

M. Raynal and A. Schiper. A suite of formal definitions for consistency criteria in distributed shared memories. In Proceedings Int Conf on Parallel and Distributed Computing (PDCS'96), pages 125--130, Dijon, France, 1996.

No context found.

Raynal, M., and Schiper, A. A suite of formal definitions for consistency criteria in distributed shared memories. In Proceedings Int Conf on Parallel and Distributed Computing (PDCS'96) (Dijon, France, 1996), pp. 125--130.

Online articles have much greater impact   More about CiteSeer.IST   Add search form to your site   Submit documents   Feedback  

CiteSeer.IST - Copyright Penn State and NEC