Computer Systems are Different!Composibility via static disciplineMoore’s lawTransistors/die doubles every ~18 monthsLithography: the driver behind transistor countCPU performanceDRAM densityDisk: Price per GByte drops at ~30-35% per yearENIACUNIVAC (Universal Automatic Computer)IBM System/360-40Cray 1: supercomputerDEC PDP-8 (1964)Apple IIIBM’s wrist watchSoftware follows hardwareCheap PervasivePervasive qualitative changeLatency improves slowlyHeat is a problemRecent Intel CPU Clock RatesThe Future: will it be painful?What went right?Computer Systems are Different!Frans Kaashoek and Robert Morris6.033 Spring 2009Composibility via static discipline•Be tolerant of inputs and strict on outputsMoore’s law“Cramming More Components Onto Integrated Circuits”, Electronics, April 1965cost per transistortransistors per dieTransistors/die doubles every ~18 monthsLithography:the driver behind transistor count• Components/area O(x2) with feature size• Total components O(a) with die area• Switching rate O(x) with feature sizeCPU performanceDRAM densityDisk: Price per GByte drops at ~30-35% per yearENIAC•1946•Only one•5000 adds/sec•20 10-digit registers•18,000 vacuum tubes•124,500 watts•Not really stored programUNIVAC (Universal Automatic Computer)•1951•46 sold•2000 ops/sec•1,000 12-digit words (mercury)•5000 tubes•$1.5 millionIBM System/360-40•1964•1.6 MHz•16-256 KB core•$225,000•Family of six•32-bit•Time-sharingCray 1: supercomputer•1976•80 sold•80 MHz•8 Mbyte SRAM•230,000 gates•$5 millionDEC PDP-8 (1964)•60,000 sold•330,000 adds/sec•4096 12-bit words•$18,000Apple II•1977•1 MHz•6502 microprocessor•4 to 48 Kilobytes RAM•$1300•Basic, VisicalcIBM’s wrist watch•2001•Linux and X11•74 Mhz CPU•8 Megabyte flash•8 Megabyte DRAM•WirelessSoftware follows hardware0102030405060Windows 3.1 (1992)Windows NT (1992)Solaris (1998)Windows 95Windows 98Windows NT 5.0 (1998)RedHat Linux 6.2 (2000)RedHat Linux 7.1 (2001)Windows XPVistaMillions of lines of source codeCheap PervasivePervasive qualitative changeyearlog (people per computer)Slide from David Culler, UC BerkeleyNumber crunchingEmbeddedSense/controlWord processingCommunicationLatency improves slowly11010010001 2 3 4 5 6 7 8 9 10 11Year #Improvement wrt year #1Moore’s law (~70% per year)DRAM access latency (~7% per year)Speed of light(0% per year)Heat is a problemRecent Intel CPU Clock Rates486PentiumPentiumProPentium IIIPentium 4Pentium 4 HTmHzThe Future: will it be painful?AMD Barcelona Quad-core chipWhat went right?•Unbounded composibility•General-purpose computers•Only need to make one thing fast•Separate arch from implementation•S/W can exploit new H/W•Cumulative R&D investment over
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