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Grading and predicting networked application behaviour

COMPUTING & CONTROL ENGINEERING JOURNAL 2000年第2期11卷 65-72页

作者： Oliver, MA Bharadia, KR Phillips, IW Parish, DJ Loughborough Univ Technol Dept Elect & Elect Engn Loughborough LE11 3TU Leics England

The user-perceived quality of an application operating over a communication network has a considerable influence on the usefulness of that application. Intuitively, it may be assumed that this quality will be related to current network performance, but in practice the relationship is often complex and difficult to determine. A scheme has been developed whereby the performance of network applications can be assessed and empirically graded for various controlled network loading conditions. Given the current network loading conditions on an operational network and information generated by the grading process, it is possible to pr-edict the performance of the network application before the application is actually run. This has the potential for reducing the amount of traffic forced on a network as a consequence of aborted connections.

关键词： user-perceived quality controlled network loading conditions communication network networked application behaviour grading telecommunication traffic software quality Software engineering techniques Network performance aborted connections operational network networked application behaviour prediction distributed systems software distributed programming network performance application usefulness software performance evaluation network traffic

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DISTRIBUTION AND ABSTRACT TYPES IN EMERALD

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IEEE TRANSACTIONS ON SOFTWARE ENGINEERING 1987年第1期13卷 65-76页

作者： BLACK, A HUTCHINSON, N JUL, E LEVY, H CARTER, L IBM CORP THOMAS J WATSON RES CTRYORKTOWN HTSNY 10598

The complexity of distributed applications is compounded by the lack of programming language support for distribution. Emerald is proposed as a solution. It is an object-based language for programming distributed subsystems and applications, whose innovative features include: 1. a single object model that is used both for programming in the small and in the large, 2. support for abstract types, and 3. an explicit notion of object location and mobility. An attempt is made to outline the goals of Emerald, relate it to previous work, and describe its type system and distribution support. By supporting abstract types, Emerald recognizes that a particular abstraction will often be implemented in several ways. This permits a system to evolve and allows the coexistence of multiple compiler-generated implementations that take advantage of distribution and locality. In addition, the concept of object mobility and call-by-move means call-by-reference semantics can be employed uniformly at all interobject interfaces, thus simplifying the construction and reconfiguration of distributed applications.

关键词： Abstract data types distributed operating system distributed programming object-oriented programming process migration type checking

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Context-aware migratory services in Ad Hoc networks

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IEEE TRANSACTIONS ON MOBILE COMPUTING 2007年第12期6卷 1313-1328页

作者： Riva, Oriana Nadeem, Tamer Borcea, Cristian Iftode, Liviu Helsinki Inst Informat Technol FIN-02015 Helsinki Finland Siemens Corp Res Princeton NJ 08540 USA New Jersey Inst Technol Dept Comp Sci Newark NJ 07012 USA Rutgers State Univ Dept Comp Sci Piscataway NJ 08854 USA

Ad hoc networks can be used not only as data carriers for mobile devices but also as providers of a new class of services specific to ubiquitous computing environments. Building services in ad hoc networks, however, is challenging due to the rapidly changing operating contexts, which often lead to situations where a node hosting a certain service becomes unsuitable for hosting the service execution any longer. We propose a novel model of service provisioning in ad hoc networks based on the concept of context-aware migratory services. Unlike a regular service that executes always on the same node, a migratory service can migrate to different nodes in the network in order to accomplish its task. The migration is triggered by changes of the operating context, and it occurs transparently to the client application. We designed and implemented a framework for developing migratory services. We built TJam, a proof- of- concept migratory service that predicts traffic jams in a given region of a highway by using only car- to- car short- range wireless communication. The experimental results obtained over an ad hoc network of personal digital assistants ( PDAs) show the effectiveness of our approach in the presence of frequent disconnections. We also present simulation results that demonstrate the benefits of migratory services in large- scale networks compared to a statically centralized approach.

关键词： mobile computing mobile applications ubiquitous computing distributed programming distributed systems

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The guardian model and primitives for exception handling in distributed systems

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IEEE TRANSACTIONS ON SOFTWARE ENGINEERING 2004年第12期30卷 1008-1022页

作者： Miller, R Tripathi, A IBM Corp Rochester MN 55901 USA Univ Minnesota Dept Comp Sci & Engn Minneapolis MN 55455 USA

This paper presents an abstraction called guardian for exception handling in distributed and concurrent systems that use coordinated exception handling. This model addresses two fundamental problems with distributed exception handling in a group of asynchronous processes. The first is to perform recovery when multiple exceptions are concurrently signaled. The second is to determine the correct context in which a process should execute its exception handling actions. Several schemes have been proposed in the past to address these problems. These are based on structuring a distributed program as atomic actions based on conversations or transactions and resolving multiple concurrent exceptions into a single one. The guardian in a distributed program represents the abstraction of a global exception handler, which encapsulates rules for handling concurrent exceptions and directing each process to the semantically correct context for executing its recovery actions. Its programming primitives and the underlying distributed execution model are presented here. In contrast to the existing approaches, this model is more basic and can be used to implement or enhance the existing schemes. Using several examples we illustrate the capabilities of this model. Finally, its advantages and limitations are discussed in contrast to existing approaches.

关键词： concurrent programming distributed programming fault tolerance

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CPDE: A Methodology for the Transparent Distribution of Centralized Smart Grid Programs

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IEEE TRANSACTIONS ON PARALLEL AND distributed SYSTEMS 2021年第2期32卷 342-354页

作者： Nguyen, Thi Thanh Quynh Bobineau, Christophe Debusschere, Vincent Giap, Quang Huy Hadjsaid, Nouredine Univ Grenoble Alpes CNRS Grenoble INP Inst EngnG2Elab F-38000 Grenoble France Univ Grenoble Alpes CNRS Grenoble INP Inst EngnLIG F-38000 Grenoble France Univ Sci & Technol Univ Danang Fac Elect Engn Danang Vietnam

Control and management in smart grids are facing many challenges such as scalability, heterogeneity and technology innovation. This requires a transformation from the traditional centralised paradigm into a distributed one. In this article, a new distributed programming methodology, called Centralised programming and distributed Execution (CPDE), is proposed. CPDE relies on (i) the abstraction of the whole system as a distributed database;(ii) the use of the Smartlog declarative and reactive rule based language for expressing data manipulation;and (iii) the automatic Smartlog rule distribution according to data distribution. It thus provides a simple and straightforward mean for distributed programming. A centralised algorithm of fair over-voltage regulation of PV systems is used as a typical smart grids study case to validate the methodology and to compare it with centralized implementations. The experiments are implemented in a real-time simulation platform with a network of Raspberry Pis. In addition to showing its correctnes and ease of use, the performance of the CPDE implementation is studied, as well as its sensitivity to the increasing number of computing units and the data distribution. Results are promising and show the clear benefits of this methodology compared to more classical implementations.

关键词： distributed programming CPDE methodology distributed database declarative language Smartlog smart grid

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Replicated data types that unify eventual consistency and observable atomic consistency

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JOURNAL OF LOGICAL AND ALGEBRAIC METHODS IN programming 2020年 114卷

作者： Zhao, Xin Haller, Philipp KTH Royal Inst Technol Sch Elect Engn & Comp Sci SE-10044 Stockholm Sweden

Strong consistency is widely used in systems such as relational databases. In a distributed system, strong consistency ensures that all clients observe consistent data updates atomically on all servers. However, such systems need to sacrifice availability when synchronization occurs. We propose a new consistency protocol, the observable atomic consistency protocol (OACP) to make write-dominant applications as fast as possible and as consistent as needed. OACP combines the advantages of (1) mergeable data types, specifically, convergent replicated data types, to reduce synchronization and (2) reliable total order broadcast to provide on-demand strong consistency. We also provide a high-level programming interface to improve the efficiency and correctness of distributed programming. We present a formal, mechanized model of OACP in rewriting logic and verify key correctness properties using the model checking tool Maude. Furthermore, we provide a prototype implementation of OACP based on Akka, a widely-used actor-based middleware. Our experimental evaluation shows that OACP can reduce coordination overhead compared to the state-of-the-art Raft consensus protocol. Our results also suggest that OACP increases availability through mergeable data types and provides acceptable latency for achieving strong consistency, enabling a principled relaxation of strong consistency to improve performance. (C) 2020 The Authors. Published by Elsevier Inc.

关键词： Atomic consistency Eventual consistency CRDT Actor model distributed programming

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Chemora: A PDE-Solving Framework for Modern High-Performance Computing Architectures

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COMPUTING IN SCIENCE & ENGINEERING 2015年第2期17卷 53-64页

作者： Schnetter, Erik Blazewicz, Marek Brandt, Steven R. Koppelman, David M. Loeffier, Frank Univ Guelph Perimeter Inst Theoret Phys Guelph ON N1G 2W1 Canada Louisiana State Univ Baton Rouge LA 70803 USA Poznan Supercomputing & Networking Ctr Applicat Dept Poznan Poland Louisiana State Univ Div Elect & Comp Engn Sch Elect Engn & Comp Sci Baton Rouge LA 70803 USA Louisiana State Univ Ctr Computat & Technol Baton Rouge LA 70803 USA

Chemora, a framework for solving systems of partial differential equations, is based on Cactus, which is heavily used in the computational relativistic astrophysics community. Chemora can help researchers study astrophysical systems such as black hole binaries, neutron stars, and core-collapse supernovae using modern high-performance computing resources.

关键词： Mathematical Model Physics High Performance Computing Scientific Computing distributed Processing Code Generation Finite Difference Methods Scientific Computing distributed programming Code Generation Physics HPC High Performance Computing

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Formal Semantics, Compilation and Execution of the GALS programming Language DSystemJ

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IEEE TRANSACTIONS ON PARALLEL AND distributed SYSTEMS 2012年第7期23卷 1240-1254页

作者： Malik, Avinash Girault, Alain Salcic, Zoran IBM Res Dublin Dublin Ireland Trinity Coll Dublin Dept Comp Sci & Stat Dublin Ireland INRIA Grenoble Rhone Alpes Grenoble France POP ART Team LIG Lab Grenoble France Univ Auckland Auckland 1 New Zealand

The paper presents a programming language, DSystemJ, for dynamic distributed Globally Asynchronous Locally Synchronous (GALS) systems, its formal model of computation, formal syntax and semantics, its compilation and implementation. The language is aimed at dynamic distributed systems, which use socket based communication protocols for communicating between components. DSystemJ allows the creation and control at runtime of asynchronous processes called clock-domains, their mobility on a distributed execution platform, as well as the runtime reconfiguration of the system's functionality and topology. As DSystemJ is based on a GALS model of computation and has a formal semantics, it offers very safe mechanisms for implementation of distributed systems, as well as potential for their formal verification. The details and principles of its compilation, as well as its required runtime support are described. The runtime support is implemented in the SystemJ GALS language that can be considered as a static subset of DSystemJ.

关键词： GALS systems distributed programming dynamic reconfiguration weak mobility formal model of computation semantics CSP pi-calculus SystemJ DSystemJ

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Cloud Technologies for Bioinformatics Applications

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IEEE TRANSACTIONS ON PARALLEL AND distributed SYSTEMS 2011年第6期22卷 998-1011页

作者： Ekanayake, Jaliya Gunarathne, Thilina Qiu, Judy Indiana Univ Sch Informat & Comp Bloomington IN 47408 USA Indiana Univ Pervas Technol Inst Bloomington IN 47408 USA

Executing large number of independent jobs or jobs comprising of large number of tasks that perform minimal intertask communication is a common requirement in many domains. Various technologies ranging from classic job schedulers to the latest cloud technologies such as MapReduce can be used to execute these "many-tasks" in parallel. In this paper, we present our experience in applying two cloud technologies Apache Hadoop and Microsoft DryadLINQ to two bioinformatics applications with the above characteristics. The applications are a pairwise Alu sequence alignment application and an Expressed Sequence Tag (EST) sequence assembly program. First, we compare the performance of these cloud technologies using the above applications and also compare them with traditional MPI implementation in one application. Next, we analyze the effect of inhomogeneous data on the scheduling mechanisms of the cloud technologies. Finally, we present a comparison of performance of the cloud technologies under virtual and nonvirtual hardware platforms.

关键词： distributed programming parallel systems performance programming paradigms

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High-performance XML modeling of parallel queries based on MapReduce framework

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CLUSTER COMPUTING-THE JOURNAL OF NETWORKS SOFTWARE TOOLS AND APPLICATIONS 2016年第4期19卷 1975-1986页

作者： Song, Kunfang Lu, Hongwei Huazhong Univ Sci & Technol Wuhan Hubei Peoples R China

With the increasing of data at an incredible rate, the development of cloud computing technologies is of critical importance to the advances of researches. MapReduce is a widely adopted computing framework for data-intensive applications running on clusters. Traditional parallel XML parsing and indexing approaches are inadequate for processing large-scale XML datasets on clusters and;therefore, we propose an approach to exploit data parallelisms in XML processing using MapReduce in Hadoop. Our solution seamlessly integrates data storage, labeling, indexing, and parallel queries to process a massive amount of XML data. Specifically, we introduce an SDN labeling algorithm and a distributed hierarchical index using DHTs. More importantly, we design an advanced two phase MapReduce solution that is able to efficiently address the issues of labeling, indexing, and query processing on big XML data. The first MapReduce phase applies filtering, labeling, index building techniques, in which each DataNode performs elements labeling using a map function and a reduce function to merge and build indexes. In the second phase, local XML queries in multiple partitions are performed in parallel using index-table-enabled B-SLCA. Our experimental results show the efficiency and effectiveness of our proposed parallel XML data approach using MapReduce Framework.

关键词： Big XML Parallel programming distributed programming MapReduce B-SLCA

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