气象应用基准测试程序MM5 Benchmark并行性能优化

由美国国家大气研究中心(NCAR)和宾夕法尼亚大学(PSU)共同开发的MM5模式是目前气象领域广泛采用的中尺度模式之一。由于MM5模式的广泛应用和计算特点,MM5 Benchmark成为了高性能计算领域衡量计算机实用性能的典型应用之一。本文介绍了MM5模式的并行计算方法,针对目前流行的Intel Itanium-2 CPU特点,在性能分析的基础上,从编译选项、代码优化、区域分解、处理机拓扑结构等方面对程序性能进行优化。实际测试结果表明,在某国产巨型机上优化后的持续计算性能最大提高20%左右。     

中尺度数值气象预报模式MM5并行性能分析与优化

气象预报模型的准确度与实时性是防震减灾工作的关键支持。MM5是成熟的并行化的中尺度数值气象预报模型。本文在阐述MM5并行模式及并行实现的基础上，具体分析了MM5在IBM eServerp Series 690主机上并行性能，并给出相应的优化方案。     

MM5在深腾6800上的移植及其数值计算方法研究

MM5是当今世界各国中短期天气及气候预测、实时预报和环境检测中使用十分广泛的数值模式,因此,如何提高软件的计算精度和计算效率是一个十分重要的问题．本文简要介绍了MM5的数值计算方法,为以后的研究提供帮助,并把MM5软件移植到深腾6800上进行并行计算．发现每当处理器增加一倍,其加速比为原来的1．5倍,可见其并行效率是较好的,值得在气象科研和业务中广泛使用．     

MM4数值模式在曙光1000机上的并行化

§１．引言 近年来,中尺度数值模式已为国内气象界熟悉,随着应用中的改进,模式物理过程的复杂化以及对分辩率的提高,其计算量显著增长,并行计算尤为重要．目前,安徽省引进一台国产曙光－１０００并行计算机,为我们提供了良好的条件． 为实现该模式的并行化,对ＭＭ４串行程序彻头彻尾的分析和改造是至关重要的．经过试验,我们在数据结构和程序结构两方面,取得了突破性进展．其结果表明并行化计算与串行程序的执行完全一致,使加速比由初期的 １： １．５提高到 １： ６．７２（１６ ＣＰＵs）初步达到满意程度, 此项工作是在中国…     

Parallel Programming of Multi-processor SoC: A HW–SW Interface Perspective

For the design of classic computers the parallel programming concept is used to abstract HW/SW interfaces during high level specification of application software. The software is then adapted to existing multiprocessor platforms using a low level software layer that implements the programming model. Unlike classic computers, the design of heterogeneous MPSoC includes also building the processors and other kind of hardware components required to execute the software. In this case, the programming model hides both hardware and software refinements. This paper deals with parallel programming models to abstract both hardware and software interfaces in the case of heterogeneous MPSoC design. Different abstraction levels will be needed. For the long term, the use of higher level programming models will open new vistas for optimization and architecture exploration like CPU/RTOS tradeoffs.     

Implementing an ODE code on distributed memory computers

In this paper, it is shown how to adapt an existing package (VODE) for solving systems of ordinary differential equations on serial computers to distributed memory parallel computers. The approach taken is based on waveform relaxation in which the problem is decomposed into a sequence of subproblems which are then solved independently using VODE on each processor. Communication between subtasks is provided by a generic software environment p4. This approach allows the development of general purpose parallel software for ODEs which is both reliable and portable.     

并行油藏模拟软件的实现及在国产高性能计算机上的应用

主要介绍了百万网格点规模的精细油藏数值模拟在国产高性能并行计算机与微机机群系统上的应用情况 .针对若干组来自于国内油田的百万网格点实际数据 ,给出了在多种国产并行机环境下的运行结果 ,并作了分析与评价 .在此基础上 ,讨论并行油藏数值模拟软件高效实现过程中遇到的关键技术 ,探讨大型软件并行化过程中经常遇到的瓶颈问题及改进方案     

基于虚拟仪器的分布式并行网络实验室

本文分析了网络实验室的类型及功能,对实验进行了分类,提出了一种基于虚拟仪器软硬件技术的分布式并行网络实验室结构。实验表明,该模型具有很好的并行性,对电工电子辅助实验教学有积极的意义。     

Massively parallel quantum computer simulator

We describe portable software to simulate universal quantum computers on massive parallel computers. We illustrate the use of the simulation software by running various quantum algorithms on different computer architectures, such as a IBM BlueGene/L, a IBM Regatta p690+, a Hitachi SR11000/J1, a Cray X1E, a SGI Altix 3700 and clusters of PCs running Windows XP. We study the performance of the software by simulating quantum computers containing up to 36 qubits, using up to 4096 processors and up to 1 TB of memory. Our results demonstrate that the simulator exhibits nearly ideal scaling as a function of the number of processors and suggest that the simulation software described in this paper may also serve as benchmark for testing high-end parallel computers.     

Intelligent technologies of high-performance computing

This article analyzes mathematical and technological problems that arise in performing computational experiments on modern high-performance computers (supercomputers). As a means of overcoming the difficulties associated with the analysis and solution of computer model problems under conditions of approximate initial data on computers with parallel architectures, intelligent technologies are proposed that are based on intelligent software supported by architectural decisions of an intelligent computer and predictive system software.     

MM:面向最终用户的Mashup移动应用开发环境

MM是一款面向最终用户的数据整合应用开发平台,它能够使没有计算机背景的普通用户利用网络上的各种资源,通过简单的可视化操作,快速地构建个性化的数据整合应用,并且可以通过手机随时随地方便地使用这些应用。重点描述了平台的框架,对非专业用户建模的支持,以及数据整合引擎的设计;提出了通过个人电脑开发、手机订制使用的Mashup应用模式;基于原型系统的案例分析验证了平台的可用性。     

大容量串行存储器MM36SB020的应用

串行Flash存储器因体积小、容量大、功耗低、价格低廉而倍受电子工程师的青睐。该文介绍了MEGAWIN公司生产的大容量串行Flash存储器MM36SB020,讲述了它的特点、结构、指令集,结合国家863项目"天然气水合物保温保压取芯钻具"具体介绍了MM36SB020在单片机系统中软硬件的设计方法,并且通过对其"忙状态"判断方法的深入研究,解决了MM36SB020因受到外界干扰而出现的状态寄存器出错的问题,大大提高了MM36SB020在实际应用中的可靠性。     

Parallel context-sensitive compilation

The searching power of massively parallel associative computers is an under used and under investigated capability that can be used to facilitate software development. This paper describes the development of a context sensitive compiler for pattern-matching languages using that searching power. The described compiler was implemented on the STARAN parallel computer and the compiled OPS5 programs were also executed on the STARAN obtaining an estimated throughput of 6000 rules per second. The described compilation of production rules into equivalent procedural rules is completely data parallel, with the degree of parallelism depending on the number of tokens in the program being compiled. During any one step of the context-sensitive analysis, the entire program is processed in constant time.     

一个系统中多单片机之间的数据交换

介绍了在一个监测或监控系统中使用多个单片机时,单片机之间的数据交换方法。重点阐述了双单片机之间数据交换的双向平行、单向平行、串行、并转串或串转平等数据交换方式,并从硬件和软件两个方面分析了保证数据交换准确性而采取的抗干扰措施。     

Test-Based Diagnosis of Faults in Data Exchange Addressing in Computer Systems Using Parallel Model

Test-based diagnosis of an arbitrary real-time computer system represented by a set of functionally related software modules executed on a single computer or concurrently on a set of computers is considered. The approach called diagnosis using a parallel model is used. An efficient procedure for test generation is proposed.     

A new MM algorithm for constrained estimation in the proportional hazards model

The constrained estimation in Cox’s model for the right-censored survival data is studied and the asymptotic properties of the constrained estimators are derived by using the Lagrangian method based on Karush–Kuhn–Tucker conditions. A novel minorization–maximization (MM) algorithm is developed for calculating the maximum likelihood estimates of the regression coefficients subject to box or linear inequality restrictions in the proportional hazards model. The first M-step of the proposed MM algorithm is to construct a surrogate function with a diagonal Hessian matrix, which can be reached by utilizing the convexity of the exponential function and the negative logarithm function. The second M-step is to maximize the surrogate function with a diagonal Hessian matrix subject to box constraints, which is equivalent to separately maximizing several one-dimensional concave functions with a lower bound and an upper bound constraint, resulting in an explicit solution via a median function. The ascent property of the proposed MM algorithm under constraints is theoretically justified. Standard error estimation is also presented via a non-parametric bootstrap approach. Simulation studies are performed to compare the estimations with and without constraints. Two real data sets are used to illustrate the proposed methods.     

Massively parallel software rendering for visualizing large-scaledata sets

We describe two highly scalable, parallel software volume-rendering algorithms - one renders unstructured grid volume data and the other renders isosurfaces. We designed one algorithm for distributed-memory parallel architectures to render unstructured grid volume data. We designed the other for shared-memory parallel architectures to directly render isosurfaces. Through the discussion of these two algorithms, we address the most relevant issues when using massively parallel computers to render large-scale volumetric data. The focus of our discussion is direct rendering of volumetric data     

A communication system for distributed computations on a network of personal computers

This paper deals with a software system PCCOM which makes it possible to simulate a distributed memory environment for parallel computations by using a local area network of personal computers. This system consists of FORTRAN subroutines that can be used from application programs. Parallel computations may be performed on a network of personal computers under DOS or any other operating system. This software package simulates, partially, the widespread PVM (Parallel Virtual Machine) package which runs under UNIX. A simple example of an application is given here.     

Basic research in computer science and software engineering at SKLCS

The State Key Laboratory of Computer Science (SKLCS) is committed to basic research in computer science and software engineering. The research topics of the laboratory include: concurrency theory, theory and algorithms for real-time systems, formal specifications based on context-free grammars, semantics of programming languages, model checking, automated reasoning, logic programming, software testing, software process improvement, middleware technology, parallel algorithms and parallel software, computer graphics and human-computer interaction. This paper describes these topics in some detail and summarizes some results obtained in recent years.