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INFORMATION PROCESSING LETTERS 1987年第5期24卷 311-316页

作者： CHANG, EJH GONNET, GH ROTEM, D UNIV WATERLOO DEPT COMP SCIWATERLOO N2L 3G1ONTARIOCANADA UNIV CALIF BERKELEY LAWRENCE BERKELEY LAB DEPT PHYS COMP SCI & MATHBERKELEYCA 94720

The authors have examined a technique for self-stabilization in a system with distributed control. Although their model is a restricted case of the system proposed by E. W. Dijkstra, the results obtained give an estimate of the cost in terms of messages needed for the system to reach a legitimate state. The number of moves which processors make is O(n**1**. **5), and the expected number of messages passed is O(n**2). Even if the processors are labelled identically except for processor n, the expected number of rounds is still n(n minus 1). Self-stabilization in distributed systems appears to be expensive.

关键词： Distributed system concurrent programming analysis of algorithms reliability

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(SM)2-II - A LARGE-SCALE MULTIPROCESSOR FOR SPARSE-MATRIX CALCULATIONS

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IEEE TRANSACTIONS ON COMPUTERS 1990年第7期39卷 889-905页

作者： AMANO, H BOKU, T KUDOH, T KEIO UNIV DEPT PHYSKOHOKU KUYOKOHAMAKANAGAWA 223JAPAN

(SM)2-II is a large-scale parallel machine dedicated to scientific computation which includes sparse matrix calculations. In order to connect thousands of microprocessors and utilize a high degree of parallelism, the whole (SM)2-II system is designed based on a simple computational model called the node and connecting-line (NC) model. The concept and the architecture of (SM)2-II are described. The NC-model and a language called node oriented concurrent C (NCC) are derived. The concurrent process controller is briefly introduced. Receiver selectable multicast (RSM) is proposed, and the structure which allows connection of a large number of processing units is described. The performance of the RSM is analyzed. Some connection structures for clusters are evaluated. An operational prototype is introduced

关键词： concurrent programming interconnection network multiprocessor parallel processing process management RSM sparse matrix

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Comparing the the performance of concurrent hash tables implemented in Haskell

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SCIENCE OF COMPUTER programming 2019年 173卷 56-70页

作者： Duarte, Rodrigo Medeiros Du Bois, Andre Rauber Pilla, Mauricio Lima Cavalheiro, Gerson Geraldo H. Sander Reiser, Renata Hax Univ Fed Pelotas PPGC Gomes Carneiro 1 BR-96010610 Pelotas RS Brazil

This paper presents seven concurrent hash table implementations in Haskell, ranging from low-level synchronization mechanisms to high-level ones such as transactional memories. The hash tables were compared using different initial sizes, load factors, data types and hash functions. We also present a case study on implementing a color palette algorithm using the hash tables. The result of the comparison between the algorithms shows that the implementation using the STM Haskell transactional memory library and fine-grain synchronization provides the best performance and good scalability, followed by the implementation using lock striping and MVars. (C) 2018 Elsevier B.V. All rights reserved.

关键词： Software transactional memory Haskell concurrent programming

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Automated Data Partitioning for Highly Scalable and Strongly Consistent Transactions

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IEEE TRANSACTIONS ON PARALLEL AND DISTRIBUTED SYSTEMS 2016年第1期27卷 106-118页

作者： Turcu, Alexandru Palmieri, Roberto Ravindran, Binoy Hirve, Sachin Virginia Tech Dept Elect & Comp Engn Blacksburg VA 24060 USA

Modern transactional processing systems need to be fast and scalable, but this means many such systems settled for weak consistency models. It is however possible to achieve all of strong consistency, high scalability and high performance, by using fine-grained partitions and light-weight concurrency control that avoids superfluous synchronization and other overheads such as lock management. Independent transactions are one such mechanism, that rely on good partitions and appropriately defined transactions. On the downside, it is not usually straightforward to determine optimal partitioning schemes, especially when dealing with non-trivial amounts of data. Our work attempts to solve this problem by automating the partitioning process, choosing the correct transactional primitive, and routing transactions appropriately.

关键词： Distributed databases code generation concurrent programming

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RENDEZVOUS FACILITIES - concurrent-C AND THE ADA LANGUAGE

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IEEE TRANSACTIONS ON SOFTWARE ENGINEERING 1988年第11期14卷 1546-1553页

作者： GEHANI, NH ROOME, WD AT&T Bell Laboratories Murray Hill NJ 07974

The concurrent programming facilities in both concurrent C and the Ada language are based on the rendezvous concept. Although these facilities are similar, there are substantial differences. Facilities in concurrent C were designed keeping in perspective the concurrent programming facilities in the Ada language and their limitations. concurrent C facilities have also been modified as a result of experience with its initial implementations. In this paper, we will compare the concurrent programming facilities in concurrent C and Ada, and show that it is easier to write a variety of concurrent programs in concurrent C than in Ada. [ABSTRACT FROM AUTHOR]

关键词： Ada concurrent C concurrent programming rendezvous

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Relaxed Concurrency Control in Software Transactional Memory

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IEEE TRANSACTIONS ON PARALLEL AND DISTRIBUTED SYSTEMS 2012年第7期23卷 1312-1325页

作者： Aydonat, Utku Abdelrahman, Tarek S. Univ Toronto Dept Elect & Comp Engn Toronto ON M5S 3G4 Canada

Some of today's TM systems implement the two-phase-locking (2PL) algorithm which aborts transactions every time a conflict occurs. 2PL is a simple algorithm that provides fast transactional operations. However, it limits concurrency in benchmarks with high contention because it increases the rate of aborts. We propose the use of a more relaxed concurrency control algorithm to provide better concurrency. This algorithm is based on the conflict-serializability (CS) model. Unlike 2PL, it allows some transactions to commit successfully even when they make conflicting accesses. We implement this algorithm in a STM system and evaluate its performance on 16 cores using standard benchmarks. Our evaluation shows that the algorithm improves the performance of applications with long transactions and high abort rates. Throughput is improved by up to 2.99 times despite the overheads of testing for CS at runtime. These improvements come with little additional implementation complexity and require no changes to the transactional programming model. We also propose an adaptive approach that switches between 2PL and CS to mitigate the overhead in applications that have low abort rates.

关键词： Transactional memory serializability concurrent programming synchronization

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Simple, space-efficient, and fairness improved FCFS mutual exclusion algorithms

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JOURNAL OF PARALLEL AND DISTRIBUTED COMPUTING 2013年第8期73卷 1029-1038页

作者： Aravind, Alex A. Univ No British Columbia Dept Comp Sci Prince George BC V2L 5P2 Canada

Let n be the number of threads that can compete for a shared resource R. The mutual exclusion problem involves coordinating these n concurrent threads in accessing R in a mutually exclusive way. This paper addresses two basic questions related to the First-Come-First-Served (FCFS) mutual exclusion algorithms that use only read-write operations: one is regarding the lower bound on the shared space requirement and the other is about fairness. The current best FCFS algorithm using read-write operations requires 5n shared bits. Could the shared space requirement be further reduced? The existing FCFS mutual exclusion algorithms assure fairness only among the threads which cross the 'doorway' sequentially. In systems with multicore processors, which are becoming increasingly common nowadays, threads can progress truly in parallel. Therefore, it is quite likely that several threads can cross the doorway concurrently. In such systems, the threads which cross the doorway sequentially may constitute only a fraction of all competing threads. While this fraction of threads follow the FCFS order, the rest of the threads have to rely on a biased scheme which always favors threads with smaller identifiers. Is there a simpler way to remove this bias to assure global fairness? This paper answers the above two questions affirmatively by presenting simple FCFS mutual exclusion algorithms using only read-write operations the first one using 3n shared bits and the latter algorithms using 4n shared bits. The resulting algorithms are simple, space-efficient, and highly fair. (C) 2013 Elsevier Inc. All rights reserved.

关键词： Mutual exclusion Process/thread synchronization concurrent programming Multicore processors Nonatomic algorithms FCFS fairness Space optimal

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The problem with threads

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COMPUTER 2006年第5期39卷 33-+页

作者： Lee, EA Univ Calif Berkeley Elect Engn Div Berkeley CA 94720 USA Univ Calif Berkeley Dept Elect Engn & Comp Sci Berkeley CA 94720 USA

For concurrent programming to become mainstream, we must discard threads as a programming model. Nondeterminism should be judiciously and carefully introduced where needed, and it should be explicit in programs.

关键词： message passing multi-threading MPI OpenMP PVM computer architectures concurrent programming data-parallel language extension general-purpose architectures message-passing libraries operating system programming languages sequential processes softwareeng

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Static analysis of cloud elasticity

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SCIENCE OF COMPUTER programming 2017年 147卷 27-53页

作者： Garcia, Abel Laneve, Cosimo Lienhardt, Michael Univ Bologna INRIA Focus Dept Comp Sci & Engn Bologna Italy Univ Torino Comp Sci Dept Turin Italy

We propose a static analysis technique that computes upper bounds of virtual machine usages in a concurrent language with explicit acquire and release operations of virtual machines. In our language it is possible to delegate other (ad-hoc or third party) concurrent code to release virtual machines (by passing them as arguments of invocations). Our technique is modular and consists of (i) a type system associating programs with behavioural types that record relevant information for resource usage (creations, releases, and concurrent operations), (ii) a translation function that takes behavioural types and returns cost equations, and (iii) an automatic off-the-shelf solver for the cost equations. A soundness proof of the type system establishes the correctness of our technique with respect to the cost equations. We have experimentally evaluated our technique using a cost analysis solver and we report some results. (C) 2017 Elsevier B.V. All rights reserved.

关键词： Resource consumption analysis Cloud computing Behavioural type system Subject reduction concurrent programming

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Eliminating synchronization faults in air traffic control software via design for verification with concurrency controllers

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AUTOMATED SOFTWARE ENGINEERING 2007年第2期14卷 129-178页

作者： Can, Aysu Betin Bultan, Tevfik Lindvall, Mikael Lux, Benjamin Topp, Stefan Middle E Tech Univ Inst Informat TR-06531 Ankara Turkey Univ Calif Santa Barbara Dept Comp Sci Santa Barbara CA 93106 USA Fraunhofer Ctr Expt Software Engn College Pk MD 20742 USA

The increasing level of automation in critical infrastructures requires development of effective ways for finding faults in safety critical software components. Synchronization in concurrent components is especially prone to errors and, due to difficulty of exploring all thread interleavings, it is difficult to find synchronization faults. In this paper we present an experimental study demonstrating the effectiveness of model checking techniques in finding synchronization faults in safety critical software when they are combined with a design for verification approach. We based our experiments on an automated air traffic control software component called the Tactical Separation Assisted Flight Environment (TSAFE). We first reengineered TSAFE using the concurrency controller design pattern. The concurrency controller design pattern enables a modular verification strategy by decoupling the behaviors of the concurrency controllers from the behaviors of the threads that use them using interfaces specified as finite state machines. The behavior of a concurrency controller is verified with respect to arbitrary numbers of threads using the infinite state model checking techniques implemented in the Action Language Verifier (ALV). The threads which use the controller classes are checked for interface violations using the finite state model checking techniques implemented in the Java Path Finder (JPF). We present techniques for thread isolation which enables us to analyze each thread in the program separately during interface verification. We conducted two sets of experiments using these verification techniques. First, we created 40 faulty versions of TSAFE using manual fault seeding. During this exercise we also developed a classification of faults that can be found using the presented design for verification approach. Next, we generated another 100 faulty versions of TSAFE using randomly seeded faults that were created automatically based on this fault classification. We u

关键词： model checking concurrent programming synchronization design patterns interfaces

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