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Where Does the Time Go in Software DSMs?—Experiences with JIAJIA

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Journal of Computer Science & Technology 1999年第3期14卷 193-205页

作者：施巍松胡伟武唐志敏 InstituteofComputingTechnology ChineseAcademyofSciencesBeijing100080PR.China

The performance gap between software DSM systems and message passing platforms prevents the prevalence of software DSM system greatly, though great efforts have been delivered in this area in the past decade. In this paper, we take the challenge to find where we should focus our efforts in the future design. The components of total system overhead of software DSM systems are analyzed in detail firstly. Based on a state-of-the-art software DSM system JIAJIA, we measure these components on Dawning parallel system and draw five important conclusions which are different from some traditional viewpoints. (1) The performance of the JIAJIA software DSM system is acceptable. For four of eight applications, the parallel ef ficiency achieved by JIAJIA is about 80%, while for two others, 70% efficiency can be obtained. (2) 40.94% interrupt service time is overlapped with waiting time. (3) Encoding and decoding diffs do not cost much time (<1%), so using hardware sup port to encode/decode diffs and send/receive messages is not worthwhile. (4) Great endeavours should be put to reduce data miss penalty and optimize synchronization operations, which occupy 11.75% and 13.65% of total execution time respectively.(5) Communication hardware overhead occupies 66.76% of the whole communication time in the experimental environment, and communication software overhead does not take much time as expected. Moreover, by studying the effect of CPU speed to system overhead, we find that the common speedup formula for distributed memory systems does not work under software DSM systems. Therefore, we design a new speedup formula special to software DSM systems, and point out that when the CPU speed increases the speedup can be increased too even if the network speed is fixed, which is impossible in message passing systems. Finally, we argue that JIAJIA system has desired scalability.

关键词： software DSM system overhead scalability communication,speedup

A Lock-Based Cache Coherence Protocol for Scope Consistency

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Journal of Computer Science & Technology 1998年第2期13卷 97-109页

作者：胡伟武 *** 施巍松 *** 唐志敏 *** 李明 *** Institute of Computing Technology Chinese Academy of Sciences Beijing P.R. China

Directory protocols are widely adopted to maintain cache coherence of distributed shared memory multiprocessors. Although scalable to a certain extent, directory protocols are complex enough to prevent it from being used in very large scale multiprocessors with tens of thousands of nodes. This paper proposes a lock-based cache coherence protocol for scope conyistency. It does not rely on directory information to maintain cache coherence. Instead, cache coherence is mailltained through requiring the releasing processor of a lock to store all write-notices generated in the associated critical section to the lock and the acquiring processor invalidates or updates its locally cached data copies according to the write notices of the lock. To evaluate the performance of the lock-based cache coherence protocol, a software DSM system named JIAJIA is built on network of workstations. Besides the lockbased cache coherence protocol, JIAJIA also characterizes itself with its shared memory organization scheme which combines the physical memories of multiple workstations to form a large shared space. Performance measurements with SPLASH2 program suite and NAS benchmarks indicate that, compared to recent SVM systems such as CVM, higher speedup is achieved by ***, JIAJIA can solve large scale problems that cannot be solved by other SVM systems due to memory size limitation.

关键词： Memory consistency cache coherence lock-based protocol directorybased protocol,scope consistency

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高速PRNS数母全加器的设计及测试原则

计算机研究与发展 1998年第3期35卷 286-286页

作者：祝明滕虹施巍松唐志敏中国科学院计算技术研究所高性能计算机研究中心哈尔滨理工大学计算中心

ＰＲＮＳ数母全加器［１，２］的研制中成功地采用了最大时间差流水线的设计原则并利用Ｆ１００Ｋ高速组件（ＥＣＬ）实现之．经功能测试后（采用自外向内的静态、动态两方面的测试方法），其工作周期为７ｎｓ．

关键词： PRNS 数母全加器加法器设计测试

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边缘智能中的协同计算技术研究

人工智能 2019年第5期 55-67页

作者：张星洲鲁思迪施巍松中国科学院大学计算技术研究所美国韦恩州立大学美国韦恩州立大学工学院 IEEE(电气和电子工程师协会) ACM(国际计算机协会) 美国韦恩州立大学计算机科学系美国韦恩州立大学移动与互联网系统结构实验室美国韦恩州立大学智能驾驶实验室

边缘智能的发展中面临着三个矛盾:智能算法的资源需求与边缘设备受限于资源之间的矛盾、服务质量与隐私保护之间的矛盾、智能任务需求多样与边缘设备能力单一之间的矛盾。通过边缘与云端、物端设备之间的协同计算可以有效地解决这些矛... 详细信息

边缘智能的发展中面临着三个矛盾:智能算法的资源需求与边缘设备受限于资源之间的矛盾、服务质量与隐私保护之间的矛盾、智能任务需求多样与边缘设备能力单一之间的矛盾。通过边缘与云端、物端设备之间的协同计算可以有效地解决这些矛盾。本文归纳了目前存在的四种协同模式,分别是:边云协同、边边协同、边物协同和云边物协同。本文针对每一种协同模式,介绍了具体的协同方式、相关技术和实现方法。随后,以典型的边缘智能场景(网联汽车和智慧家庭)为例,分析协同计算的优势。最后,本文提出为了实现边缘智能中的真正协同需要面对的几个挑战。

关键词：人工智能应用分布式协同计算智能算法神经网络模型云计算中心安全和隐私深度神经网络

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基于边缘计算的新型视频监控系统展望

自动化博览 2018年第12期35卷 60-63页

作者：施巍松孙辉陈彦明美国韦恩州立大学安徽大学

面向公共安全领域内的视频监控系统主要应对违法犯罪及社会管理等公共安全问题。传统视频监控系统具有前端摄像机内置计算资源较少、数据量较大、传输带宽延迟较高、目标跟踪效率较低等不足,为此,需构建基于边缘计算的新型视频监控系统... 详细信息

面向公共安全领域内的视频监控系统主要应对违法犯罪及社会管理等公共安全问题。传统视频监控系统具有前端摄像机内置计算资源较少、数据量较大、传输带宽延迟较高、目标跟踪效率较低等不足,为此,需构建基于边缘计算的新型视频监控系统的软硬件服务平台。本文主要从针对视频监控的边缘计算系统、基于边缘计算的视频监控系统协同处理、基于边缘计算的摄像机网络目标跟踪以及基于边缘计算的突发事件处理等方面来介绍边缘计算在视频监控系统中的应用及其优势。

关键词：视频监控系统展望目标跟踪安全问题社会管理违法犯罪公共安全计算资源

CA-DTS:A Distributed and Collaborative Task Scheduling Algorithm for Edge Computing Enabled Intelligent Road Network

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Journal of Computer Science & Technology 2023年第5期38卷 1113-1131页

作者：胡世红罗渠元李光辉施巍松叶保留 Key Laboratory of Water Big Data Technology of Ministry of Water Resources Houhai UniversityNanjing 210098China School of Computer and Information Houhai UniversityNanjing 210098China School of Information Science and Technology Southwest Jiaotong UniversityChengdu 611756China School of Artificial Intelligence and Computer Science Jiangnan UniversityWuci 214122China Department of Computer and Information Sciences University of DelawareNewarkDE 19716U.S.A National Key Laboratory for Novel Software Technology Nanjing UniversityNanjing 210093China

Edge computing enabled Intelligent Road Network(EC-IRN)provides powerful and convenient computing services for vehicles and roadside sensing *** continuous emergence of transportation applications has caused a huge burden on roadside units(RSUs)equipped with edge servers in the Intelligent Road Network(IRN).Collaborative task scheduling among RSUs is an effective way to solve this ***,it is challenging to achieve collaborative scheduling among different RSUs in a completely decentralized *** this paper,we first model the interactions involved in task scheduling among distributed RSUs as a Markov *** that multi-agent deep reinforcement learning(MADRL)is a promising approach for the Markov game in decision optimization,we propose a collaborative task scheduling algorithm based on MADRL for EC-IRN,named CA-DTS,aiming to minimize the long-term average delay of *** reduce the training costs caused by trial-and-error,CA-DTS specially designs a reward function and utilizes the distributed deployment and collective training architecture of counterfactual multi-agent policy gradient(COMA).To improve the stability of performance in large-scale environments,CA-DTS takes advantage of the action semantics network(ASN)to facilitate cooperation among multiple *** evaluation results of both the testbed and simulation demonstrate the effectiveness of our proposed *** with the baselines,CA-DTS can achieve convergence about 35%faster,and obtain average task delay that is lower by approximately 9.4%,9.8%,and 6.7%,in different scenarios with varying numbers of RSUs,service types,and task arrival rates,respectively.

关键词： edge computing deep reinforcement learning task scheduling vehicular edge computing

VPI:Vehicle Programming Interface for Vehicle Computing

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Journal of Computer Science & Technology 2024年第1期39卷 22-44页

作者：吴宝福仲任王昱心万健张纪林施巍松 School of Computer Science and Technology Hangzhou Dianzi UniversityHangzhou 310018China Department of Computer Science Wayne State UniversityDetroitMI 48202U.S.A Department of Computer and Information Sciences University of DelawareNewarkDE 19716U.S.A

The emergence of software-defined vehicles(SDVs),combined with autonomous driving technologies,has en-abled a new era of vehicle computing(VC),where vehicles serve as a mobile computing ***,the interdisci-plinary complexities of automotive systems and diverse technological requirements make developing applications for au-tonomous vehicles *** simplify the development of applications running on SDVs,we propose a comprehen-sive suite of vehicle programming interfaces(VPIs).In this study,we rigorously explore the nuanced requirements for ap-plication development within the realm of VC,centering our analysis on the architectural intricacies of the Open Vehicu-lar Data Analytics Platform(OpenVDAP).We then detail our creation of a comprehensive suite of standardized VPIs,spanning five critical categories:Hardware,Data,Computation,Service,and Management,to address these evolving pro-gramming *** validate the design of VPIs,we conduct experiments using the indoor autonomous vehicle,Ze-bra,and develop the OpenVDAP prototype *** comparing it with the industry-influential AUTOSAR interface,our VPIs demonstrate significant enhancements in programming efficiency,marking an important advancement in the field of SDV application *** also show a case study and evaluate its *** work highlights that VPIs significantly enhance the efficiency of developing applications on *** meet both current and future technologi-cal demands and propel the software-defined automotive industry toward a more interconnected and intelligent future.

关键词： software-defined vehicle(SDV) vehicle computing(VC) vehicle programming interface(VPI) au-tonomous system

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面向云文件系统的隔离性度量方法研究

计算机工程与科学 2017年第7期39卷 1227-1233页

作者：周丽张天明任祖杰施巍松万健张纪林李尤慧子叶正杭州电子科技大学计算机学院浙江杭州310018 韦恩州立大学计算机科学系浙江科技学院浙江杭州310023

随着云计算的快速发展,云文件系统在云计算基础设施中扮演着越来越重要的角色。尽管目前业界已有不少面向云文件系统的性能评测工具,但大多数评测工具仅关注于传统的系统性能指标,比如IOPS和吞吐量,难以评估云文件系统在多租户环境下的... 详细信息

随着云计算的快速发展,云文件系统在云计算基础设施中扮演着越来越重要的角色。尽管目前业界已有不少面向云文件系统的性能评测工具,但大多数评测工具仅关注于传统的系统性能指标,比如IOPS和吞吐量,难以评估云文件系统在多租户环境下的性能隔离性。由于云环境I/O负载的动态性和异构性,所以准确评估云文件系统的隔离性变得更加具有挑战性。提出了一种新型的云文件系统隔离性度量模型,并在一个基准测试工具Porcupine中进行了实现。Porcupine通过模拟真实负载特征的I/O请求,实现对负载与性能的准确仿真并提高文件系统的测试效率。通过对Ceph文件系统的实验,验证了所提出的隔离性度量模型的有效性及准确性。

关键词：性能隔离云文件系统基准测试多租户环境

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专题:边缘计算技术及其应用

中兴通讯技术 2019年第3期 1-1页

作者：郑纬民潘毅施巍松清华大学计算机科学与技术系美国乔治亚州立大学计算机科学系美国韦恩州立大学计算机科学系中国自动化学会边缘计算专业委员会 ACM/IEEE国际边缘计算大会(SEC)

内容导读近年来,以云计算模型为核心的集中式处理模式已无法高效处理边缘设备产生的数据,边缘计算因此应运而生。"边缘计算(edge computing)"一词由美国太平洋西北国家实验室的R. LAMOTHE于2013年在一个两页纸的内部报告中首次提出。201... 详细信息

内容导读近年来,以云计算模型为核心的集中式处理模式已无法高效处理边缘设备产生的数据,边缘计算因此应运而生。"边缘计算(edge computing)"一词由美国太平洋西北国家实验室的R. LAMOTHE于2013年在一个两页纸的内部报告中首次提出。2016年5月,美国韦恩州立大学施巍松教授团队给出了边缘计算的正式定义:"边缘计算是指在网络边缘执行计算的一种新型计

关键词：云计算中心云计算模型