Computer Organization and Design slide.pdf

8/14/2019 Computer Organization and Design slide.pdf

1/25

Computer Organization andComputer Organization andDesignDesign

Dr. Arjan DurresiLouisiana State University

Baton Rouge, LA 70803

CSC3501 FALL07Louisiana State University 1- Introduction - 1

urresi csc. su.e u

These slides are available at:http://www.csc.lsu.edu/~durresi/CSC3501_07/

OverviewOverview

How

What

When


Why


2/25

OverviewOverview

How am I going to gradeyou?

What are we going to cover?

When areyou going to do it?


Whyyou should take this course?

GradingGrading Learning-centered course:

The first priority: Maximize learning

our gra e w e en on ow muc youhave learned

3 Quizzes (2 best out of three) 55%

Activity in the class (15%)

Questions and discussions in class give you


points and improve the quality of teaching Homework (30%)


3/25

Frequently Asked QuestionsFrequently Asked Questions Yes, I do use curve. Your grade depends

upon the performance of the rest of the class. All homeworks are due at the beginning of the

next class. All late submissions must be preapproved. All quizzes are open-book and extremely time

limited. Quizzes consist of numerical as well as


multiple-choice (true-false) questions.

There is negative grading on incorrectmultiple-choice questions.

What Is This Course About?What Is This Course About?

Understanding of basic issues, concepts,principles of Computer Architecture.

Organizational paradigms that determine:

Capabilities, Performance and theSuccess

Relationship between hardware and software


current computers.


4/25

Text BookText Book

David A. Patterson, John L. Hennessy"Computer Organization and Design TheHardware/Software Interface,"


Third Edition, 2005,

ISBN:1-55860-604-1 . This book is very comprehensive. I will

follow it as much as possible.

Office HoursOffice Hours Tuesday and Thursday: 3:00 to 4:00 PM

and by appointments

Office: 291 Coates Hall

Telephone: (225)-578-3902

Email: [email protected]

Course web page:

: ~


. . . _

GTA:

Email:


5/25

IntroductionIntroduction This course is all about how computers work

But what do we mean by a computer? Different types: desktop, servers, embedded devices

, , ,

Different manufacturers: Intel, Apple, IBM, Microsoft,Sun

Different underlying technologies and different costs!

Analogy: Consider a course on automotive vehicles

Many similarities from vehicle to vehicle (e.g., wheels)


Huge differences from vehicle to vehicle (e.g., gas vs.electric)

Best way to learn:

Focus on a specific instance and learn how it works

While learning general principles and historical perspectives

Course OutlineCourse Outline Course overview and topics

Introduction to Computer Architecture

Instruction Set Architecture

Arithmetic for Computers

Performance of Computer Systems

Basics of Digital Logic Design

Register Files and Memory

ALU Design


Designing of MIPS Processor (Single-Cycle) Designing of MIPS Processor (Multi-Cycle)

Pipelining

Memory Hierarchy


6/25

Why learn this stuff?Why learn this stuff? You want to call yourself a computer scientist

You want to build software people use (need performance)

You need to make a purchasing decision or offer expert advice

Both Hardware and Software affect performance:

Algorithm determines number of source-level statements

Language/Compiler/Architecture determine machineinstructions

(Chapter 2 and 3)


Processor/Memory determine how fast instructions areexecuted

(Chapter 5, 6, and 7)

Assessing and Understanding Performance in Chapter 4

What is a computer?What is a computer? Components: input (mouse, keyboard)

out ut dis la rinter

memory (disk drives, DRAM, SRAM, CD)

network

Our primary focus: the processor (datapathand control)


Impossible to understand by looking at each

transistor

We need...


7/25

AbstractionAbstraction

Delving into the depthsreveals more information

An abstraction omitsunneeded detail,helps us cope withcomplexity


What are some of thedetails that appear inthese familiarabstractions?

How do computers work?How do computers work? Need to understand abstractions such as:

Applications software Systems software

Machine Language Architectural Issues: i.e., Caches, Virtual Memory, Pipelining Sequential logic, finite state machines Combinational logic, arithmetic circuits Boolean logic, 1s and 0s Transistors used to build logic gates (CMOS)


em con uctors con use to u trans stors Properties of atoms, electrons, and quantum dynamics

So much to learn!


8/25

Forces on Computer ArchitectureForces on Computer Architecture

Technology ProgrammingLanguages

Computer

Archi tecture

Operating

Appl ications


Systems

History

(A = F / M)

Amazing UnderlyingAmazing UnderlyingTechnology ChangeTechnology Change



9/25

Historical PerspectiveHistorical Perspective ENIAC built in World War II was the first general purpose

computer Used for computing artillery firing tables 80 feet long by 8.5 feet high and several feet wide

ac o t e twenty g t reg sters was eet ong Used 18,000 vacuum tubes Performed 1900 additions per second

Since then:

Moores Law:


rans s or capac y ou esevery 18-24 months

Below Your ProgramBelow Your Program



10/25

Operating SystemOperating System

Handling basic input and output operations Allocating storage and memory

Providing for sharing the computer amongmultiple applications using it simultaneously


Below YourBelow YourProgramProgram

High level languages:

natural way

2) Improve programmer

productivity

3) Allows programs to be

independent of the computer



11/25

Computer OrganizationComputer Organization


The five classic components: 1) Input, 2) Output, 3) Memory,4) Datapath 5) Control

Inside Pentium 4Inside Pentium 4



12/25

Communicating with otherCommunicating with other

computerscomputers Networks are the backbone of the current

computing system

Information is exchanged among computers athigh speed

Resource sharing. Especially expensiveresources.


Nonlocal access. Freedom for users

Optical, wireless

The Chip Manufacturing ProcessThe Chip Manufacturing Process



13/25

An 8An 8--inch wafer containing Pentiuminch wafer containing Pentium

4 processors4 processors


Pentium 4 ProcessorPentium 4 Processor



14/25

Measurement and EvaluationMeasurement and EvaluationArchi tecture is an i terative process

-- searching the space of possible designs

-- at all levels of computer systemsDesign

Cost /Performance

Analysi s

Creativity


Good IdeasGood IdeasMediocre Ideas

Bad Ideas

hat is Computer Architecturehat is Computer ArchitectureOperating

System

App licat ion

I/O systemInstr. Set Proc.

Digital Design

Circuit Design

Instruction SetArchi tecture

Datapath & Control

Layout


Coordination of many levels of abstraction

Under a rapidly changing set of forces

Design, Measurement, and Evaluation


15/25

Computer ArchitectureComputer Architecture A modern meaning of the term computer architecture

covers three aspects of computer design:

ns ruc on se arc ec ure,

computer organization and

computer hardware.

Instruction Set Architecture - ISA refers to theactual programmer-visible machine interface such asinstruction set, registers, memory organization and


exception handling. Two main approaches: RISC andCISC architectures.

A computer organization and computer hardware aretwo components of the implementation of a machine.

Computer ArchitectureComputer Architecture Computer organization includes the high-level aspectsof a design, such as the memory system, the busstructure, and the design of the internal CPU (where

, ,implemented).

Computer hardware refers to the specifics of amachine, included the detailed logic design and thepackaging technology of the machine.

For many years the interaction between ISA andimplementations was believed to be small, and


imp ementation issues were not a major ocus indesigning instruction set architecture. In the 1980s, it becomes clear that both the

difficulty and inefficiency of pipelining could beincreased by instruction set architecturecomplications.


16/25

Tasks of Computer Architects Computer architects must design a computer to meet

functional requirements as well as price, power, andperformance goals. Often, they also have to determinewhat the functional requirements are, which can be a

. Once a set of functional requirements has been

established, the architect must try to optimize thedesign. Here are three major application areas andtheir main requirements:

Desktop computers: focus on optimizing cost-performance as measured by a single user, with


little regard for program size or powerconsumption,

Server computers focus on availability, scalability,and throughput cost-performance,

Embedded computers driven by price and oftenpower issues, plus code size is important.

Classes of ComputingClasses of Computing



17/25

Major ArchitecturesMajor Architectures


Rapid Rate of Improvements

Now, less than one thousand dollars purchasesa personal computer that has more

, ,disk storage than a computer bought in 1980for one million dollars.

For many applications, the highest-performance microcomputers of todayoutperform the supercomputers of less than


years ago. This rapid rate of improvement has come from

two forces: technology used to build computers and innovations in computer design.


18/25

Growth of capacity per DRAMGrowth of capacity per DRAM

chip over timechip over time


Performance of WorkstationsPerformance of Workstations



19/25

A take on Moores LawA take on Moores Law

100,000,000Bi t- level par all eli sm Inst ruct ion- level T hread-l evel (?)

Transistors

100,000

1,000,000

10,000,000

i80286

i80386

R2000

Pentium

R10000

R3000


1,000

10,000

1970 1975 1980 1985 1990 1995 2000 2005

i4004

i8008i8080

i8086

Technology TrendsTechnology Trends Clock Rate: ~30% per year Transistor Density: ~35%

: ~

Transistors per chip: ~55%

Total Performance Capability: ~100%

by the time you graduate...

3x clock rate (4-6 GHz)


10x transistor count (1 Billion transistors) 30x raw capability

plus 16x dram density, 32x disk density


20/25

100Supercomputers

Performance TrendsPerformance Trends

Performance

1

10

Minicomputers

Mainframes

Microprocessors


0.1

1965 1970 1975 1980 1985 1990 1995

Technology Trends Integrated circuit logic technology a growth in

transistor count on chip of about 55% per year.

60% per year, while cycle time has improved veryslowly, decreasing by about one-third in 10 years. Costhas decreased at rate about the rate at which densityincreases.

Magnetic disc technology disk density has beenrecently improving more then 100% per year, while


. Network technology Latency and bandwidth are

important, though recently bandwidth has beenprimary focus. Internet infrastructure in the U.S. hasbeen doubling in bandwidth every year.


21/25

Developments in Computer Design

During the first 25 years of electronic computersboth forces, technology and innovations in computer

.

Then, during the 1970s, computer designers werelargely dependent upon integrated circuit technology,with roughly 35% growth per year in processorperformance.

In the last 20 year, the combination of innovations in


led sustained growth in performance at an annual rate

of over 55%. In this period, the main source ofinnovations in computer design has come from RISC-style pipelined processors.

Growth in Microprocessor Performance



22/25

RISC Architecture

After 1985, any computer announced has beenof RISC architecture. RISC designers focusedon two cr t ca per ormance tec n ques ncomputer design:

the exploitation of instruction-levelparallelism, first through pipelining andlater through multiple instruction issue,


t e use o cac e, irst in simp e orms an

later using sophisticated organizations andoptimizations.

RISC ISA Characteristics All operations on data apply to data in registers and

typically change the entire register;

store operations that move data from memory to aregister or to memory from a register, respectively;

A small number of memory addressing modes; The instruction formats are few in number with all

instructions typically being one size; Lar e number of re isters;


These simple properties lead to dramaticsimplifications in the implementation of advancedpipelining techniques, which is why RISC architectureinstruction sets were designed this way.


23/25

RISC and CISC Architecture RISC Reduced Instruction Set Computer CISC Complex (and Powerful) Instruction Set

Computer What does MIPS stand for?

Stages. MIPS processor is one of the first RISCprocessors. Again, all processors announced after1985 have been of RISC architecture.

What is the main example of CISC architectureprocessor?

Answer: Intel IA-32 processors (in over 90%com uters .


Intel IA-32 processors, from 80386 processor inearly 80s to Pentium IV today, and the next one to beintroduced this or next year, are of CISCarchitecture. All Intel IA-32 processors are having asa base the Identical instruction set architecturedesigned in early 1980s.

Intel IA-32 Processors

The improvements in technology have allowed the latest IntelIA-32 processors (of CISC architecture) to adopt manyinnovations first pioneered in the RISC design.

Since 1995, Pentium rocessors consist of a front end rocessorand a RISC-style processor.

The front end processor fetches and decodes Intel IA-32complex instructions and maps them into microinstructions.

A microinstruction is a simple instruction used in sequence toimplement a more complex instruction. Microinstructions lookvery much as RISC instructions.

Then the RISC-st le rocessor executes microinstructions.


As a transistor counts soured, the overhead (in transistors) ofinterpreting the more complex IA-32 architecture becomesnegligible.


24/25

VAX vs. MIPS processors This graph compares results of VAX 8700 (CISC) and

MIPS M2000 (RISC) processors that execute nineprograms from SPEC89 benchmarks.

CPU time = Instruction count * CPI / Clock rate_ _


Comparison of VAX and MIPSprocessors The graph indicates that, on average, MIPS executed about

twice as many instructions as VAX. (Bad for MIPS)

T e grap in icates t at, on average, t e CPI or t e VAX wasabout six times larger than that for MIPS. (Bad for VAX)

CPI the average number of clock cycles per instruction

CPI = CPU_clock_cycles_for_a_program Instruction_count

CPU time a time to execute a given program

CPU time = Instruction_count *CPI Clock_rate


,better performance (measured by CPU time) than VAX.


25/25

SummarySummary

There will be a lot of self-reading

Get ready to work hard


Thank You!Thank You!


Documents

Computer Organization and Design slide.pdf