检索结果-南通市图书馆

Multi-threaded code generation from Signal program to openmp*

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Computer Science 2013年第5期7卷 617-626页

作者： Kai HU Teng ZHANG Zhibin YANG State Key Laboratory of Software Development Environment Beihang University Beijing 100191 China School of Computer Science and Engineering Beihang University Beijing 100191 China IRIT-CNRS Universite de Toulouse Toulouse 31062 France

The use of multi-core processors will become a trend in safety critical systems. For safe execution of multi- threaded code, automatic code generation from formal spec- ification is a desirable method. Signal, a synchronous lan- guage dedicated for the functional description of safety crit- ical systems, provides soundness semantics for determinis- tic concurrency. Although sequential code generation of Sig- nal has been implemented in Polychrony compiler, deter- ministic multi-threaded code generation strategy is still far from mature. Moreover, existing code generation methods use certain multi-thread library, which limits the cross plat- form executions. openmp* is an application program inter- face （API） standard for parallel programming, supported by several mainstream compilers from different platforms. This paper presents a methodology translating Signal program to openmp*-based multi-threaded C code. First, the intermedi- ate representation of the core syntax of Signal using syn- chronous guarded actions is defined. Then, according to the compositional semantics of Signal equations, the Signal pro- gram is synthesized to dependency graph （DG）. After par- allel tasks are extracted from dependency graph, the Signal program can be finally translated into openmp*-based C code which can be executed on multiple platforms.

关键词： multi-thread synchronous language Signal,code generation openmp*

openmp*DSP:Extending openmp* to Program Multi-Core DSPs

在线全文

学校读者我要写书评

暂无评论

Journal of Computer Science & Technology 2014年第2期29卷 316-331页

作者：何江舟陈文光陈光日郑纬民汤志忠叶寒栋 Department of Computer Science and Technology Tsinghua University Huawei Technologies Co. Ltd.

Multi-core digital signal processors （DSPs） are widely used in wireless telecommunication, core network transcoding, industrial control, and audio/video processing technologies, among others. In comparison with general-purpose multi-processors, multi-core DSPs normally have a more complex memory hierarchy, such as on-chip core-local memory and non-cache-coherent shared memory. As a result, efficient multi-core DSP applications are very difficult to write. The current approach used to program multi-core DSPs is based on proprietary vendor software development kits （SDKs）, which only provide low-level, non-portable primitives. While it is acceptable to write coarse-grained task-level parallel code with these SDKs, writing fine-grained data parallel code with SDKs is a very tedious and error-prone approach. We believe that it is desirable to possess a high-level and portable parallel programming model for multi-core DSPs. In this paper, we propose openmp*DSP, an extension of openmp* designed for multi-core DSPs. The goal of openmp*DSP is to fill the gap between the openmp* memory model and the memory hierarchy of multi-core DSPs. We propose three classes of directives in openmp*DSP, including 1） data placement directives that allow programmers to control the placement of global variables conveniently, 2） distributed array directives that divide a whole array into sections and promote the sections into core-local memory to improve performance, and 3） stream access directives that promote big arrays into core-local memory section by section during parallel loop processing while hiding the latency of data movement by the direct memory access （DMA） of a DSP. We implement the compiler and runtime system for openmp*DSP on PreeScale MSC8156. The benchmarking results show that seven of nine benchmarks achieve a speedup of more than a factor of 5 when using six threads.

关键词： openmp* multi-core digital signal processor data parallelism Long Term Evolution

Implementation of openmp* Parallelization of Rate-Dependent Ceramic Peridynamic Model

在线全文

学校读者我要写书评

暂无评论

Computer Modeling in Engineering & Sciences 2022年第10期133卷 195-217页

作者： Haoran Zhang Yaxun Liu Lisheng Liu Xin Lai Qiwen Liu Hai Mei Department of Engineering Structure amd Mechanics Wuhan University of TechnologyWuhan430070China Hubei Key Laboratory of Theory and Application of Advanced Materials Mechanics Wuhan University of TechnologyWuhan430070China

A rate-dependent peridynamic ceramic model,considering the brittle tensile response,compressive plastic softening and strain-rate dependence,can accurately represent the dynamic response and crack propagation of ceramic ***,it also considers the strain-rate dependence and damage accumulation caused by compressive plastic softening during the compression stage,requiring more computational resources for the bond force evaluation and damage ***,the openmp* parallel optimization of the rate-dependent peridynamic ceramicmodel is ***,themodules that compute the interactions betweenmaterial points and update damage index are vectorized and ***,the numerical examples are carried out to simulate the dynamic response and fracture of the ceramic plate under normal ***,the speed-up ratio and computational efficiency by multi-threads are evaluated and discussed to demonstrate the reliability of parallelized *** results reveal that the totalwall clock time has been significantly reduced after optimization,showing the promise of parallelization process in terms of accuracy and stability.

关键词： Ceramic penetration behavior rate-dependent peridynamic model openmp* parallel computing

openmp*-based parallel transient stability simulation for large-scale power systems

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2012年第10期55卷 2837-2846页

作者： JIANG QuanYuan JIANG Han College of Electrical Engineering Zhejiang UniversityHangzhou 310027China

This paper provides an openmp*-based parallel Very Dishonest Newton(VDHN) algorithm with variable step size,running transient stability simulations(TSA) on multi-core *** the framework of simultaneous solution method of TSA,the step-size control strategy is used according to the local truncation error theory ***,computation of the generation units,which is the most time-consuming part of the simulation,is dynamically dispatched to several cores using an α dynamic scheduling scheme to obtain workload balancing based on *** to the convergence of Newton-type iterations,an adaptive Jacobian update control strategy is applied to reduce the sequential part of the simulation and the overhead generated by *** large scale test cases verify the validity and practicability of the proposed parallel algorithm,showing that the proposed approach achieves high speed-up and a considerable reduction in parallel overheads.

关键词： transient stability parallel compute openmp* Very Dishonest Newton(VDHN) step-size control scheduling scheme adaptive Jacobian update control

openmp* on Networks of Workstations for Software DSMs

在线全文

学校读者我要写书评

暂无评论

Journal of Computer Science & Technology 2002年第1期17卷 90-100页

作者：章锋陈国良张兆庆 University of Science and Technology of China Hefei 230027 P.R. China Institute of Computing Technology The Chinese Academy of Sciences Beijing 100080 P.R. China

This paper describes the implementation of a sizable subset of openmp* on networks of workstations (NOWs) and the source-to-source openmp* compiler (AutoPar) is used for the JIAJIA home-based shared virtual memory system (SVM). The paper suggests some simple modifications and extensions to the openmp* standard for the difference between SVM and SMP (symmetric multi processor), at which the openmp* specification is aimed. The openmp* translator is based on an automatic parallelization compiler, so it is possible to check the correctness of the semantics of openmp* programs which is not required in an openmp*-compliant implementation. AutoPar is measured for five applications including both programs from NAS Parallel Benchmarks and real applications on a cluster of eight Pentium II PCs connected by a 100Mbps switched Ethernet. The evaluation shows that the parallelization by annotating openmp* di rectives is simple and the performance of generated JIAJIA code is still acceptable on NOWs.

关键词： openmp* NOW SVM JIAJIA NPB (NAS parallel benchmark)

MPI/openmp*-Based Parallel Solver for Imprint Forming Simulation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computer Modeling in Engineering & Sciences 2024年第7期140卷 461-483页

作者： Yang Li Jiangping Xu Yun Liu Wen Zhong Fei Wang School of Mechanical Engineering Jiangsu UniversityZhenjiang212016China School of Mechanical Engineering Wuhan Polytechnic UniversityWuhan430023China Shenyang Mint Company Limited Shenyang110092China

In this research,we present the pure open multi-processing(openmp*),pure message passing interface(MPI),and hybrid MPI/openmp* parallel solvers within the dynamic explicit central difference algorithm for the coining process to address the challenge of capturing fine relief features of approximately 50 *** such precision demands the utilization of at least 7 million tetrahedron elements,surpassing the capabilities of traditional serial programs previously *** mitigate data races when calculating internal forces,intermediate arrays are introduced within the openmp* *** helps ensure proper synchronization and avoid conflicts during parallel ***,in the MPI implementation,the coins are partitioned into the desired number of *** division allows for efficient distribution of computational tasks across multiple *** simulation examples are conducted to compare the three solvers with serial programs,evaluating correctness,acceleration ratio,and parallel *** results reveal a relative error of approximately 0.3%in forming force among the parallel and serial solvers,while the predicted insufficient material zones align with experimental ***,speedup ratio and parallel efficiency are assessed for the coining process *** pureMPI parallel solver achieves a maximum acceleration of 9.5 on a single computer(utilizing 12 cores)and the hybrid solver exhibits a speedup ratio of 136 in a cluster(using 6 compute nodes and 12 cores per compute node),showing the strong scalability of the hybrid MPI/openmp* programming *** approach effectively meets the simulation requirements for commemorative coins with intricate relief patterns.

关键词： Hybrid MPI/openmp* parallel computing MPI openmp* imprint forming

Parallel Seismic Modeling Based on openmp*+AVX and Optimization Strategy

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Earth Science 2019年第4期30卷 843-848页

作者： Wenge Liu Fan Wang Huawei Zhou School of Geoscience and Technology Southwest Petroleum UniversityChengdu 610500China Department of Earth and Atmospheric Sciences University of HoustonHouston TX 77004USA

This paper describes parallel simulation of the memory/computation-intensive acoustic wave equation with CPU template buffer optimization. Considering the 8-core CPU shared storage platform as an example,we obtain a one-time speed-up ratio of 6.7× compared with the serial program by using a coarse-grained openmp* parallel scheme. Then,data is vectorized on the template buffer using the single instruction-multiple data(SIMD) technique to further exploit the computing potential of the CPUs. We apply an 8-channel parallel vector to simulate seismic wavefields with the 256-bit advanced vector extensions(AVX) instruction set. This increases the computing bandwidth,thus eliminating a significant volume of the computing instructions and obtaining a secondary speed-up ratio of 3–7×. In addition,we use 32-byte data alignment,shortest data direction vectorization,and loop tiling optimization algorithm to achieve faster program execution. Finally,we analyze the factors affecting the secondary speed-up of AVX through three-dimensional modeling experiments with the salt *** results indicate that the memory,cache,and register can better cooperate with each other and the speed-up is increased by optimizing the AVX algorithm.

关键词： forward modeling openmp* AVX parallel optimization

Parallelization and performance tuning of molecular dynamics code with openmp*

在线全文

学校读者我要写书评

暂无评论

Journal of Central South University of Technology 2006年第3期13卷 260-264页

作者：白树仁冉丽萍鲁奎麟 High Performance Computing Center Hunan University Changsha 410012 China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China Department of Applied Physics Hunan UniversityChangsha 410082China

An openmp* approach was proposed to parallelize the sequential molecular dynamics(MD) code on shared memory machines. When a code is converted from the sequential form to the parallel form, data dependence is a main problem. A traditional sequential molecular dynamics code is anatomized to find the data dependence segments in it, and the two different methods, i.e., recover method and backward mapping method were used to eliminate those data dependencies in order to realize the parallelization of this sequential MD code. The performance of the parallelized MD code was analyzed by using some performance analysis tools. The results of the test show that the computing size of this code increases sharply form 1 million atoms before parallelization to 20 million atoms after parallelization, and the wall clock during computing is reduced largely. Some hot-spots in this code are found and optimized by improved algorithm. The efficiency of parallel computing is 30% higher than that of before, and the calculation time is saved and larger scale calculation problems are solved.

关键词： system analysis molecular dynamics parallel computing performance tuning openmp*

Time-dependent Density Functional-based Tight-bind Method Efficiently Implemented with openmp* Parallel and GPU Acceleration

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Physics 2013年第6期26卷 635-645,I0003页

作者： Guo-hong Fan Ke-li Han Guo-zhong He State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical Physics ChineseAcademy of Sciences Dalian 116023 China

The time-dependent density functional-based tight-bind （TD-DFTB） method is implemented on the multi-core and the graphical processing unit （GPU） system for excited state calcu-lations of large system with hundreds or thousands of atoms. Sparse matrix and openmp* multithreaded are used for building the Hamiltonian matrix. The diagonal of the eigenvalue problem in the ground state is implemented on the GPUs with double precision. The GPU- based acceleration fully preserves all the properties, and a considerable total speedup of 8.73 can be achieved. A Krylov-space-based algorithm with the openmp* parallel and CPU acceleration is used for finding the lowest eigenvalue and eigenvector of the large TDDFT matrix, which greatly reduces the iterations taken and the time spent on the excited states eigenvalue problem. The Krylov solver with the GPU acceleration of matrix-vector product can converge quickly to obtain the final result and a notable speed-up of 206 times can be observed for system size of 812 atoms. The calculations on serials of small and large systems show that the fast TD-DFTB code can obtain reasonable result with a much cheaper computational requirement compared with the first-principle results of CIS and full TDDFT calculation.

关键词： Density-functional theory Tight-binding method Time-dependent densityfunctional theory Excited state Graphical processing unit Krylov iterative algorithm Sparse matrix openmp*