Chapter 2 Computer Evolution and Performance
Contents • Key points • Brief history of computers —Vacuum tubes —Transistors —ICs • Designing for performance —microprocessor speed —performance balance • Pentium and PowerPC evolution
Key points • Evolution of computers — increased processor speed — decreased component size — increased memory size — increased I/O capacity and speed • Increased processor speed — size of the components has been reduced — use of pipelining and parallel execution — use of speculative execution technique • Balancing the performance of various elements — gains in performance in one area should not be handicapped by a lag in other areas — processor speed vs. memory access time – caches, wider data paths
ENIAC - background • Electronic Numerical Integrator And Computer —first general-purpose electronic digital computer • Eckert and Mauchly • University of Pennsylvania • Trajectory tables for weapons • Started 1943 • Finished 1946 —Too late for war effort • Used until 1955
ENIAC - details • Decimal machine(not binary) • 20 accumulators of 10 digits —each digit is represented by 10 vacuum tubes • Programmed manually by switches • 18,000 vacuum tubes • 30 tons • 15,000 square feet • 140 KW power consumption • 5,000 additions per second
von Neumann Machine • Stored Program concept —not setting switches manually from outside —but storing the instructions and data inside • John von Neumann —IAS computer – Started 1946, completed 1952 – Prototype of all subsequent computers • General structure of IAS computer —Main memory storing programs and data —ALU operating on binary data —Control unit interpreting instructions —I/O equipment operated by control unit
Structure of von Neumann machine
IAS - details • 1000 x 40 bit words —Binary number —2 x 20 bit instructions • Set of registers (storage in CPU) —Memory Buffer Register —Memory Address Register —Instruction Register —Instruction Buffer Register —Program Counter —Accumulator —Multiplier Quotient
Structure of IAS – detail
IAS - instructions • Total of 21 instructions(Table 2.1) —Data transfer —Unconditional branch —Conditional branch —Arithmetic —Address modify
Commercial Computers - UNIVAC • 1947 - Eckert-Mauchly Computer Corporation —UNIVAC I (Universal Automatic Computer) —US Bureau of Census 1950 calculations —Became part of Sperry-Rand Corporation • Late 1950s - UNIVAC II —Faster, more memory —Upward compatible with the older machines
Commercial Computers - IBM • Punched-card processing equipment • 1953 - 701 —IBM’s first stored program computer —Scientific calculations • 1955 - 702 —Business applications • Lead to 7000 series
Transistors • Replaced vacuum tubes • Smaller • Cheaper • Less heat dissipation • Solid State device made from Silicon • Invented 1947 at Bell Labs • William Shockley et al.
Transistor Based Computers • Second generation machines • NCR & RCA produced small transistor machines • IBM followed with 7000 series • DEC - 1957 —Produced PDP-1 —mini-computer phenomenon began
IBM 7094 • From 700 series to 7094 series —increased performance —increased capacity —lower cost
Microelectronics • What do we need for a digital computer? — they need to perform storage, movement, processing, and control functions — gates and memory cells • Gate — a device that implements a simple logical function • Memory cell — a device that can store one bit of data • Which functions are supported by which device? — Storage : provided by memory cells — Processing : provided by gates — Movement : provided by the interconnection(paths) between components — Control : control signals can be carried by the interconnection
Computer Generations • Vacuum tube - 1946-1957 • Transistor - 1958-1964 • Small scale integration - 1965 on —Up to 100 devices on a chip • Medium scale integration - to 1971 —100-3,000 devices on a chip • Large scale integration - 1971-1977 —3,000 - 100,000 devices on a chip • Very large scale integration - 1978 to date —100,000 - 100,000,000 devices on a chip • Ultra large scale integration —Over 100,000,000 devices on a chip
Moore’s Law • Increased density of components on a chip • Gordon Moore - cofounder of Intel • Number of transistors on a chip will double every year • Since 1970’s development has slowed a little — Number of transistors doubles every 18 months • Consequences of Moore’s law — Cost of a chip has remained almost unchanged — Higher packing density means shorter electrical paths, increasing operating speed — Smaller size, making it more convenient to place in a variety of environments — Reduced power and cooling requirements — Fewer interconnections increases reliability
Grow th in CPU Transistor Count
IBM 360 series • 1964 • Replaced & not compatible with 7000 series —to produce a system with new IC technology • First planned “family” of computers —Similar or identical instruction sets —Similar or identical O/S —Increasing speed —Increasing number of I/O ports (i.e. more terminals) —Increasing memory size —Increasing cost
DEC PDP-8 • 1964 • First minicomputer —could not do everything the mainframe could • Small enough to sit on a lab bench • $16,000 —$100k+ for IBM 360 • Use bus structure —Omnibus
DEC - PDP-8 Bus Structure I/O Main Memory I/O Console CPU Module Module Controller OMNIBUS
Semiconductor Memory • 1970 : from core to ICs • Fairchild • Size of a single core could hold 256 bits • Non-destructive read(compared to destructive core) • Much faster than core • Capacity approximately doubles each year —since 1970, 11 generations —1K, 4K, 16K, 64K, 256K, 1M, 4M, 16M, 64M, 256M, 1G
Speeding it up • Besides the number of transistors in a chip… —Pipelining —On board cache – L1 & L2 cache —Branch prediction – if the guess is right most of the time, we can prefetch the correct instructions —Data flow analysis – analyze which instructions are dependent on which – create an optimized schedule of instructions —Speculative execution – speculatively execute instructions ahead of their actual appearance
Performance Mismatch • Processor speed increased • Memory capacity increased • Memory speed lags behind processor speed
DRAM and Processor Characteristics
Solutions • Increase number of bits retrieved at one time —Using wide bus data paths • Change DRAM interface —Cache • Reduce frequency of memory access —More complex cache • Increase interconnection bandwidth —High speed buses —Hierarchy of buses
Pentium Evolution (1) • 8080 — first general purpose microprocessor — 8 bit data path — Used in the first personal computer – Altair • 8086 — much more powerful — 16 bit data path and registers — instruction cache for prefetching few instructions — 8088 (8 bit external bus) used in the first IBM PC • 80286 — 16 MB memory addressable • 80386 — Intel’s first 32 bit processor — Support multitasking
Pentium Evolution (2) • 80486 —sophisticated powerful cache and instruction pipelining —built-in math coprocessor • Pentium —superscalar technique – multiple instructions executed in parallel • Pentium Pro —increased superscalar organization —aggressive register renaming —branch prediction —data flow analysis —speculative execution
Pentium Evolution (3) • Pentium II —MMX technology – graphics, video & audio processing • Pentium III —Additional floating point instructions for 3D graphics • Pentium 4 —Further floating point and multimedia enhancements • Itanium —64 bit machine with IA-64 architecture —details in Chap 15 • See Intel web pages for detailed information on processors
Pow erPC (1) • A superscalar RISC system —companies involved – IBM, Motorola, Apple —used in Apple Macintosh machines • 601 —32 bit machine • 603 —intended for low-end desktop and portable computers • 604 —uses advanced superscalar techniques
Pow erPC (2) • 620 —intended for high-end servers —full 64 bit architecture – 64 bit registers and data paths • 740/750 —also known as G3 processor —two level cache • G4 —increased parallelism and speed
Internet Resources • http://www.intel.com/ —Search for the Intel Museum • http://www.ibm.com • http://www.dec.com • Charles Babbage Institute • PowerPC • Intel Developer Home
Problem Solving Assignment 1 • Solve the following problems of Chapter 2: — 1
Recommend
More recommend
