“平衡”是系统研发的一个永恒的主题
“平衡”是系统研发的一个永恒的主题
计算机 系统和应用进程的三个阶段。计算机是为“计算(computing)”「而研制的（1930s-1990s一CPU芯片，操作系统，存贮系统，编译软件，高性能计算。。一物质和物理世界被转变为数字世界，快速计算和深度分析一人类社会有了前所未有的科技突破：气象，新型材料，。。。。·计算机是为“网络（connectivity)”而研制的（1990s一2010s）一互联网和无线上网是一个全新数据世界的基础.1981-2017:Bandwidth:from50Kbpsto100Pbps(2Mtimes)1981-2017:#ofdevices/user:from0.1to 10 (100times)网络电话，微博，QQ，微信，网上购物，网上查询，。。。·计算机是为“数据中心(data)”而研制的（从21世纪开始)一今天大数据的爆炸并不是已有的物理和物质的数字世界的一个延续一这个新的数据世界精确地记录和追踪人类自身的行为一有史以来90%的数据是过去两年产生的2
计算机 系统和应用进程的三个阶段 • 计算机是为 “计算 (computing)” 而研制的(1930s -1990s) – CPU芯片，操作系统，存贮系统，编译软件，高性能计算。 – 物质和物理世界被转变为数字世界， 快速计算和深度分析 – 人类社会有了前所未有的科技突破：气象，新型材料， 。 • 计算机是为 “网络 (connectivity)” 而研制的 (1990s – 2010s) – 互联网和无线上网是一个全新数据世界的基础: • 1981-2017: Bandwidth: from 50K bps to 100P bps (2 M times) • 1981-2017: # of devices/user: from 0.1 to 10 (100 times) • 网络电话， 微博，QQ, 微信，网上购物， 网上查询， 。 • 计算机是为 “数据中心 (data)” 而研制的 (从21世纪开始) – 今天大数据的爆炸并不是已有的物理和物质的数字世界的一个延续 – 这个新的数据世界精确地记录和追踪人类自身的行为 – 有史以来90%的数据是过去两年产生的 2
Two Trends in IT R&D·DomainSpecific Software Development-Softwareis designed,developed &maintainedindomainareas-Manynon-softwareFortune5o0companiesowndomainsoftware:Amazon (Retail):cloudsoftware. Walmart (grocery shopping): data analytics software Google (Internet search): big data system software and Android: Facebook (social networks): big data warehouse software (Hive), Presto:ExxonMobil (oilCompany):3DseismicdataprocessingsoftwareSoftware defined Infrastructure (hardware)-Definingapplications'values andfunctionsontopofhardware-Translating users'requirements into best hardware performance-Software defined storage,software definednetworks,datacenterdefinedcloud
Two Trends in IT R&D • Domain Specific Software Development – Software is designed, developed & maintained in domain areas – Many non-software Fortune 500 companies own domain software • Amazon (Retail): cloud software • Walmart (grocery shopping): data analytics software • Google (Internet search): big data system software and Android • Facebook (social networks): big data warehouse software (Hive), Presto • ExxonMobil (oil Company): 3D seismic data processing software • . • Software defined Infrastructure (hardware) – Defining applications’ values and functions on top of hardware – Translating users’ requirements into best hardware performance – Software defined storage, software defined networks, datacenter defined cloud . 3
MajorResources inComputing and NetworkSystemsGoodNewsinsupplyCPU cycles:oversupplied for many applicationsMemory bandwidth: improved dramaticallyMemory capacity:increasingly large and at low cost.//O bandwidth:improved dramaticallyDisk capacity: huge and at very low cost. Cluster and Internet bandwidths: very richBad News indemandCPU cycles per Watt decreases. (less energy efficient)Cache capacity: always limited.Improvementofdataaccesslatenciesveryslow.- Networking and energy costs are increasingly highAdam Smith: commodity price is defined by an“invisiblehand"inthe market.Weneed to balanceOversupplied cycles,largestorage capacity,fastnetworksHigh demand of low latency accesses, low energy cost
Major Resources in Computing and Network Systems ▪ Good News in supply ▪ CPU cycles: oversupplied for many applications. ▪ Memory bandwidth: improved dramatically. ▪ Memory capacity: increasingly large and at low cost. ▪ I/O bandwidth: improved dramatically. ▪ Disk capacity: huge and at very low cost. ▪ Cluster and Internet bandwidths: very rich. ▪ Bad News in demand ▪ CPU cycles per Watt decreases. (less energy efficient). ▪ Cache capacity: always limited. ▪ Improvement of data access latencies very slow. ▪ Networking and energy costs are increasingly high ▪ Adam Smith: commodity price is defined by an “invisible hand” in the market. We need to balance ▪ Oversupplied cycles, large storage capacity, fast networks ▪ High demand of low latency accesses, low energy cost
Moore's Law Driven Computing Research (IEEE spectrum, May2008)4.0GHz40010years ofdarkageof parallelcomputing,3.5 GHzCPU-memorygap isthemajor concern3.0 GHz300QuadcoreDRAM(costof1MBinUSS)Dualcore2.5GHzadsosro2002.0GHzSirgleprocessor1.5GHz1.0GHz100500MHzCostof1MBofDRAMin2006:$0.0009Processorspeedin1971;400KHz0197120001975198019851990199520052008个个Neweraofmulticorecomputing25year ofgoldenageofparallel computingMemoryproblemcontinues5
5 Moore’s Law Driven Computing Research (IEEE Spectrum, May 2008) hi 25 year of golden age of parallel computing 10 years of dark age of parallel computing, CPU-memory gap is the major concern. New era of multicore computing Memory problem continues