DPOS: A metalanguage and programming environment for parallel processing

This paper describes and illustrates a structured programming metalanguage (DPOS) and graphical programming environment for generating and debugging high-level distributed MIMD parallel programs. DPOS introduces an innovative message-passing model and also recursive graphical definition of parallel process networks. It also provides programming and debugging at the meta language level that is portable across implementation languages. The initial development focus of DPOS is to provide a parallel development system for Lisp-based, symbolic and artificial intelligence programs as part of the MAYFLY parallel processing project. The DPOS environment also generates source code and provides a simulation system for graphical debugging and animation of the programs in graph form.     

Visual programming support for graph‐oriented parallel/distributed processing

GOP is a graph‐oriented programming model which aims at providing high‐level abstractions for configuring and programming cooperative parallel processes. With GOP, the programmer can configure the logical structure of a parallel/distributed program by constructing a logical graph to represent the communication and synchronization between the local programs in a distributed processing environment. This paper describes a visual programming environment, called VisualGOP, for the design, coding, and execution of GOP programs. VisualGOP applies visual techniques to provide the programmer with automated and intelligent assistance throughout the program design and construction process. It provides a graphical interface with support for interactive graph drawing and editing, visual programming functions and automation facilities for program mapping and execution. VisualGOP is a generic programming environment independent of programming languages and platforms. GOP programs constructed under VisualGOP can run in heterogeneous parallel/distributed systems. Copyright © 2005 John Wiley & Sons, Ltd.     

Estimating and optimizing performance for parallel programs

The article describes P³T, a parameter-based performance prediction tool that estimates performance for parallel programs running on distributed-memory parallel architectures. P³ T has been carefully designed to address all of the above performance estimation issues. To achieve high estimation accuracy, P ³T aggressively exploits compiler analysis and optimization information. Our method is based on modeling loop iteration spaces, array access patterns, and data distributions by intersection and volume operations on n-dimensional polytopes. The most critical architecture-specific factors, such as cache line sizes, number of cache lines available, routing policy, start-up times, message transfer time per byte, and so forth, are modeled to reflect the performance impact of the target machine. P³T has been developed in the context of the Vienna Fortran Compilation Systems (VFCS), a state-of-the-art parallelization tool for distributed-memory systems. VFCS translates Fortran programs into explicitly parallel message-passing programs. P ³T successfully guides the interactive and automatic restructuring of programs under this system. The article describes the underlying compilation and programming model and discusses the most critical design decisions made for P³T; in addition, it outlines the implementation of the parallel program parameters. Also described are the VFCS context under which P³T is applied and the P³T graphical user interface     

多机系统的体系结构描述语言MS—HADL

本文提出了一种面向多机系统的计算机硬件描述语言MS-HADL.该语言以高级程序语言C为基础,提供专门描述计算机与计算机之间、计算机与外界之间联系的工具,可以较好地描述具有并行特性的系统.     

A graphical development and debugging environment for parallel programs

To provide high-level graphical support for PVM (Parallel Virtual Machine) based program development, a complex programming environment (GRADE) is being developed. GRADE currently provides tools to construct, execute, debug, monitor and visualize message-passing parallel programs. It offers a high-level graphical programming abstraction mechanism to construct parallel applications by introducing a new graphical language called GRAPNEL. GRADE also provides the programmer with the same graphical user interface during the program design and debugging stages. A distributed debugging engine (DDBG) assists the user in debugging GRAPNEL programs on distributed memory computer architectures. Tape/PVM and PROVE support the performance monitoring and visualization of parallel programs developed in the GRADE environment.     

SIMCAN: A flexible, scalable and expandable simulation platform for modelling and simulating distributed architectures and applications

In this paper we propose a new simulation platform called SIMCAN, for analyzing parallel and distributed systems. This platform is aimed to test parallel and distributed architectures and applications. The main characteristics of SIMCAN are flexibility, accuracy, performance, and scalability. Thence, the proposed platform has a modular design that eases the integration of different basic systems on a single architecture. Its design follows a hierarchical schema that includes simple modules, basic systems (computing, memory managing, I/O, and networking), physical components (nodes, switches, …), and aggregations of components. New modules may also be incorporated as well to include new strategies and components. Also, a graphical configuration tool has been developed to help untrained users with the task of modelling new architectures. Finally, a validation process and some evaluation tests have been performed to evaluate the SIMCAN platform.     

A flexible and easy to use molecular biology workbench efficiently developed in Tcl/Tk

We describe the design and implementation of a workbench for molecular biology that allows the easy integration of analysis tools. The software is implemented in Tcl/Tk using the [incr Tcl] extension that provides object‐oriented programming. The program is called tkGDE and consists of four main parts. The sequence editor allows the user to perform basic editing operations on biomolecule sequences. The graphical annotation editor gives the user a graphical overview of all annotated features of a sequence. The output manager retains information on the results produced by the analysis tools. The bundle control allows several tools to run automatically, passing data from one tool to the next. Tools are integrated into the system by describing their properties in a configuration file, which drastically reduces the time needed for integration. We present results proving that Tcl/Tk has been misjudged to be slow and unsuited for large projects. To achieve sufficient performance we exploited special features of Tcl/Tk, namely idle tasks and the capabilities built into the Tk canvas widget. The system consists of more than 34000 lines of [incr Tcl] code in 182 classes. The whole development process took about one person‐year. Copyright © 2000 John Wiley & Sons, Ltd.     

Economic performance assessment of advanced process control with LQG benchmarking

Economic performance assessment of advanced process control is conducted to investigate performance potentials that can be obtained by control system improvement. An optimization-based approach for economic performance assessment of the constrained process control is integrated with the LQG benchmark in this paper. By explicitly incorporating uncertainty into the performance assessment problem, economic performance evaluation can be formulated as a stochastic optimization problem, which helps to identify the opportunity to improve profitability of the process by taking appropriate risk levels. Using the LQG benchmark to estimate achievable variability reduction through control system improvement, the proposed method provides an estimate of both the performance that can be expected from the improved control system and the operating condition that delivers the improved performance. The results obtained can serve as a tool for control engineers to make decisions on control system tuning and/or upgrading. The proposed algorithm is illustrated via simulation examples as well as an industrial example.     

Lightweight Online Performance Monitoring and Tuning with Embedded Gossip

Understanding and tuning the performance of large-scale long-running applications is difficult, with both standard trace-based and statistical methods having substantial shortcomings that limit their usefulness. This paper describes a new performance monitoring approach called Embedded Gossip (EG) designed to enable lightweight online performance monitoring and tuning. EG works by piggybacking performance information on existing messages and performing information correlation online, giving each process in a parallel application a weakly consistent global view of the behavior of the entire application. To demonstrate the viability of EG, this paper presents the design and experimental evaluation of two different online monitoring systems and an online global adaptation system driven by Embedded Gossiping. In addition, we present a metric system for evaluating the suitability of an application to EG-based monitoring and adaptation, a general architecture for implementing EG-based monitoring systems, and a modified global commit algorithm appropriate for use in EG-based global adaptation systems. Together, these results demonstrate that EG is an efficient low-overhead approach for addressing a wide range of parallel performance monitoring tasks and that results from these systems can effectively drive online global adaptation.     

An interactive tool for design,simulation, verification,and synthesis of protocols

We have developed a user-friendly CAD graphical tool for the design, verification, simulation, and synthesis of protocols based on an interactive tool for Petri net and state diagram designs. Special features of this tool are: the capability of modeling both control and data flows, reduction and analysis, simulation of network behavior and performance, coding (parametrized protocols and automatic implementation), synthesis (two party protocol and ordinary Petri nets), animation and flexible design. Since it is Petri-net based, it allows simulation during all design phases and has extensive applications such as parallel debugging and simulation, expert systems, etc. Future enhancements of this tool are also discussed.     

A language and system for the construction and tuning of parallel programs

The programming of efficient parallel software typically requires extensive experimentation with program prototypes. To facilitate such experimentation, any programming system that supports rapid prototyping of parallel programs should provide high-level language primitives with which programs can be explicitly, statically, or dynamically tuned with respect to performance and reliability. Such language primitives should be able to refer conveniently to the information about the executing program and the parallel hardware required for tuning. Such information may include monitoring data about the current or previous program or even hints regarding appropriate tuning decisions. Language primitives and an associated programming system for program tuning are presented. The primitives and system have been implemented, and have been tested with several parallel applications on a network of Unix workstations.<>     

面向多领域的可视化应用开发平台MOVADP

ＭＯＶＡＤＰ是一个面向多领域的可视化应用开发平台，文中主要介绍了该平台的软件结构和实现技术，ＭＯＶＡＤＰ以数据流机制为核心，采用可视编程技术，为用户开发可视化应用提供了一个文凭交互的模块级图形编程环境，与同类平台相比，ＭＯＶＡＤＰ的特点在于，引入了ＩＦＴＨＥＮ－ＥＬＳＥ，ＷＨＩＬＥ－ＬＯＯＰ等控制结构，支持用户构建复杂的可化应用流图；支持“ｌａｚｙｅｖａｌｕａｔｉｏｎ”命令驱动方式下的流图局部运行     

A methodology for transparent knowledge specification in a dynamic tuning environment

The increasing use of parallel/distributed applications demands a continuous support to take significant advantages from parallel power. This includes the evolution of performance analysis and tuning tools which automatically allows for obtaining a better behavior of the applications. Different approaches and tools have been proposed and they are continuously evolving to cover the requirements and expectations of users. One such tool is MATE (Monitoring Analysis and Tuning Environment), which provides automatic and dynamic tuning for parallel/distributed applications. The knowledge used by MATE to analyze and take decisions is based on performance models which include a set of performance parameters and a set of mathematical expressions modeling the solution of the performance problem. These elements are used by the tuning environment to conduct the monitoring and analysis steps, respectively. The tuning phase depends on the results of the performance analysis. This paper presents a methodology to specify performance models. Each performance model specification can be automatically and transparently translated into a piece of software code encapsulating the knowledge to be straightforwardly included in MATE. Applying this methodology, the user does not have to be involved in the implementation details of MATE, which makes the usage of the tool more transparent. Copyright © 2011 John Wiley & Sons, Ltd.     

TOWARDS PARALLEL PROGRAMMING BY TRANSFORMATION: THE FAN SKELETON FRAMEWORK*

A Functional Abstract Notation (FAN) is proposed for the specification and design of parallel algorithms by means of skeletons - high-level patterns with parallel semantics. The main weakness of the current programming systems based on skeletons ii that the user is still responsible for finding the most appropriate skeleton composition for a given application and a given parallel architecture

We describe a transformational framework for the development of skeletal programs which is aimed at filling this gap. The framework makes use of transformation rules which are semantic equivalences among skeleton compositions. For a given problem, an initial, possibly inefficient skeleton specification is refined by applying a sequence of transformations. Transformations are guided by a set of performance prediction models which forecast the behavior of each skeleton and the performance benefits of different rules. The design process is supported by a graphical tool which locates applicable transformations and provides performance estimates, thereby helping the programmer in navigating through the program refinement space. We give an overview of the FAN framework and exemplify its use with performance-directed program derivations for simple case studies. Our experience can be viewed as a first feasibility study of methods and tools for transformational, performance-directed parallel programming using skeletons.     

Reconfigurable simulator using graphical user interface (GUI) and object-oriented design for OFDM systems

In this paper, a design of a new object-oriented simulation environment and graphical user interface (GUI) for versatile orthogonal frequency division multiplexing (OFDM) systems is presented. This is achieved using high-level design, parallelism and usability for the simulation environment. GUI interface can serve as a learning/research tool for students or practiced professionals to investigate particular designs. It is evident that OFDM systems intended to be used in dynamic environments must be tested under various conditions in order to be designed for optimality. Hence, a simulation design is proposed coupling the GUI, parallelism, and high-level object-oriented design techniques to be beneficial to the researcher. A high-level design and GUI layouts of the proposed simulator is shown in details. Important OFDM parameters needed for reconfiguration of transmitter components, channel condition parameters, and receiver components are discussed. In addition, this paper provides a simple technique to implement simulation partitioning for increased parallel performance of reconfigurable object-oriented OFDM simulators. This simple technique applies to scenarios where there is disproportionate simulation duration between different OFDM configurations. It is shown to decrease total simulation time considerably.     

Scopira: an open source C++ framework for biomedical data analysis applications

In many biomedical research laboratories, data analysis and visualization algorithms are typical prototypes using an interpreted programming language. If performance becomes an issue, they are ported to C and integrated with interpreted systems, not fully utilizing object‐oriented software development. This paper presents an overview of Scopira, an open source C++ framework suitable for biomedical data analysis and visualization. Scopira provides high‐performance end‐to‐end application development features, in the form of an extensible C++ library. This library provides general programming utilities, numerical matrices and algorithms, parallelization facilities, and graphical user interface elements. Copyright © 2008 John Wiley & Sons, Ltd.     

Modeling and analysis of a mail processing plant using Petri nets

This article outlines the utilization of Petri nets as a computerized process modeling and analysis tool for the study of the Edmonton Mail Processing Plant (MPP). Development of new systems or designing improvement in existing system—such as the MPP—are some of the challenges faced by decision makers and managers on a regular basis in the industry. In order to make prudent decisions, modeling and analysis of the underlying processes that constitute new or existing systems has become essential. Usually process modeling and analysis is performed by initially developing a graphical portrayal of the process and then by dynamically studying the response of the process to external and internal factors. In this article an overview of Petri net based process modeling and analysis is provided. Petri net is a formal graphical modeling tool that can be efficiently utilized as a process modeling and analysis tool because it can graphically portray and dynamically simulate a process in an integrated manner. The objective of this article is to highlight the symbolic graphic format and dynamic simulation capabilities of Petri nets. The article contributes significantly in the area of computer based decision making and provides value to practicing engineers and project managers who manage complex tasks.     

一种利用UML的Petri网软件实现方法

Petri网既是一种图形化建模工具，又是一种形式化数学工具。Petri网具有对并发、并行、分布、异步系统进行验证仿真的能力。但是，Petri网是用来描述和分析要开发的系统模型的工具。不是计算机的实现工具，必须要通过一定的方法才能将Petri网用软件来实现。由于UML(统一建模语言)具有友善的用户界面，易于编程实现，故提出一种利用UML作为过渡的Petri网软件实现方法。     

The “Smart” simulation environment – A tool-set to develop new cache coherency protocols

“Smart” is a new system-level simulation environment that was developed in order to evaluate and improve algorithms for distributed and parallel systems. In this paper we focus our discussion on the developing of new cache coherency mechanisms that were optimized to handle system-level effects such as process switching and task migration. The developing of new cache coherency protocols is a good example to demonstrate many of the important features of Smart, since system-level events have a major influence on the effectiveness of different cache coherency policies and the overall performance of multicache systems. The Smart simulation environment was built as a separate layer that extends existing multi-processing simulators, so we could take the advantage of using mature and reliable simulation engines. Smart also provides a friendly graphical user interface (GUI) that allows: (1) control of different system parameters and mechanisms such as the cache coherency protocol type, cache organization, scheduling policies of processes and threads, etc., (2) simulation of the execution of shared-memory parallel architecture and measuring different systems' performance parameters and (3) use as a powerful visual based debugging tool. Although this paper presents a version of Smart which is dedicated for shared-bus architectures, other libraries of the tool can simulate different parallel and distributed architectures as well.