1Computer System DesignLecture 1: IntroductionProf. R. Iris BaharEN164January 24, 2007Reading: 1.1, 1.2, 1.5, 1.6 EN164Lecture 1-2Course Contents• Introduction to computer system design–Assumes some basic knowledge of computer architecture and/or logic design• Topics–Measuring performance/cost/power– Designing instruction sets– Instruction level parallelism, dynamic and static– Memory hierarchy– Multiprocessors– Storage systems and networks• Course prerequisites–EN163. Digital Electronics Systems Design, and/or CS31or– Consent of instructorEN164Lecture 1-3Course Administration• Instructor: R. Iris [email protected] Barus & HolleyOffice Hours: M 2:00-3:00 & Th 9:00-10:00• Head TA: Mickey Tadesse [email protected] Hrs: TBD• Undergrad TA: Brian Reggiannini [email protected]• Labs: Lab assignments 1-3 should be completed in the electronics lab (B&H 192). Lab 4 will use the PCs in the computer lab• URL: http://www.lems.brown.edu/cad/courses/EN164/index.htm• Text: Hennessy, Patterson “Computer Architecture, A Quantitative Approach”, 4thEdition, Morgan Kaufman, 2007EN164Lecture 1-4Grading Information• Grade Distribution–Homework 10%– Lab Assignments 30%– Midterm Exam 20%• Friday, March 16th, in class– Final Exam 35%• Wednesday, May 18th, 2:00pm – 5:00pm– Class Participation 5%• Please let me know ASAP about exam conflictsEN164Lecture 1-5Other Important Announcements• There will be no class on–Friday, January 26th(this Friday)• I will be out of town on–Monday, April 2nd– Monday, Wednesday, April 16thand 18th• We will make up class later in the semester, as needed, or find a substitute for the class–Announcements will be made later in the semesterEN164Lecture 1-6Why are you taking this course?1. I liked my previous computer systems / digital design course and wanted to learn more 2. I want to be a lead architect on the next flagship CPU3. It will prepare me for research on modern microarchitecture.4. Everyone else was signing up for it5. I need a 100-level EN course to fulfill my Sc.B. requirements…and it was the only one that fit my schedule6. I want to learn more about hardware aspects of computer design so I can be a more effective systems designer Operating systems Distributed computing Computer networks Compiler construction VLSI system design System verification/validation2EN164Lecture 1-7Historical Perspectives• The Decade of the 1970’s: “Birth of Microprocessors”–Programmable Controller– Single-Chip Microprocessors– Personal Computers (PC)• The Decade of the 1980’s: “Quantitative Architecture”–Instruction Pipelining– Fast Cache Memories– Compiler Considerations– Workstations• The Decade of the 1990’s: “Instruction-Level Parallelism”–Superscalar,Speculative Microarchitectures– Aggressive Compiler Optimizations– Low-Cost Desktop SupercomputingWhat about this decade?EN164Lecture 1-8Evolution of Single-Chip μPC100,000 20-2,0000.2-20< 0.2MIPS/MFLOPS10 (?)0.9- 2.00.1-0.9< 0.1Instruction/Cycle10GHz20M-1GHz2-20MHz0.2-2MHzClock Frequency1B1M-100M100K-1M10K-100KTransistor Count20101990’s1980’s1970’sEN164Lecture 1-9Performance Growth in Perspective • Doubling every 18 months (1982-2000): –total of 3,200X– Cars travel at 176,000 MPH; get 64,000 miles/gal.– Air travel: L.A. to N.Y. in 5.5 seconds (MACH 3200)– Wheat yield: 320,000 bushels per acre• Doubling every 24 months (1971-2001): –total of 36,000X– Cars travel at 2,400,000 MPH; get 600,000 miles/gal.– Air travel: L.A. to N.Y. in 0.5 seconds (MACH 36,000)– Wheat yield: 3,600,000 bushels per acreUnmatched by any other industry!! [John Crawford, Intel, 1993]EN164Lecture 1-10Key Enabling Technologies:• CMOS VLSI:– Submicron feature sizes: 0.8μ Æ 0.6μ Æ 0.3μ Æ 0.25μ Æ 0.18μ– Metal layers: 3 Æ 4 Æ 5 Æ 6 Æ 7 (copper)– Power supply voltage: 5v Æ 3.3v Æ 2.4v Æ1.8v• CAD Tools:– Interconnect simulation and critical path analysis– Clock signal propagation analysis– Process simulation and yield analysis/learning• Microarchitecture:– Superpipelined and superscalar machines– Speculative and dynamic microarchitectures– Simulation tools and emulation systems• Compilers:– Extraction of instruction-level parallelism– Aggressive and speculative code scheduling– Object code translation and optimizationEN164Lecture 1-11Microprocessor Performance15X performance growth can be attributed just to architectural innovationsEN164Lecture 1-12Concepts: Definition One• Computer architecture–attributes of a system visible to a programmer: instruction set,data types, I/O mechanisms, addressing of memory• Computer organization–hardware details transparent to a programmer: operational units and their interconnections, peripheral interfaces, memory system3EN164Lecture 1-13An Example• Architectural issue: Does the computer have a multiply instruction or not?• Organizational issue: Does the computer have a special multiply unit or does it repeatedly use the add unit?EN164Lecture 1-14Concepts: Definition Two• Computer architecture =Instruction set architecture +Machine organization• Instruction set architecture–The actual programmer-visible instruction set.– The interface between the hardware and low-level software• Two different processors can have identical instruction sets, but can have very different pipelines and cache organizations.EN164Lecture 1-15Instruction Set Architecture• Organization of storage: registers, memory• Representations of data• Instruction set (types of operands)• Instruction formats• Modes of addressing and accessing data• Exceptional conditionsEN164Lecture 1-16Instruction Set Architecture• Many processors today are based on the same instruction set architecture.• Advantage: –Same code can run on many different machines• Disadvantage: –may prevent using new innovations – May require major hardware support to carry over from one generation to the next.• Think of Intel’s IA32 Instruction set architectureEN164Lecture 1-17Machine Organization• Implementation, capabilities and performance characteristics of functional units• Interconnections of these units• Information flows between these units• Control of information flow• Hardware description languages such as VHDL and Verilog are designed for describing the machine