Chapter 2 Computer Evolution and Performance Contents Key points - - PowerPoint PPT Presentation

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

OMNIBUS Console Controller CPU Main Memory I/O Module I/O Module

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:

—

Reading Assignment 1

• Read and report on the following paper from the

research literature. Your report should be one to two pages long; three-quarters of the report should summarize the paper, and one-quarter of the report should be a critique. Introduce your report with a formal citation of the paper, using the format found in the References section of the textbook.

• Flynn, M. “What’s Ahead in Computer Design?”

Euromicro ‘97 Proceedings, September 1997. Http://umunhum.stanford.edu/papers.html