Chapter 1 of Computer abstraction and organization.

1. Chapter 1
Computer Abstractions
and Technology
Dr. Nivine Güler
[Adapted from Computer Organization and Design,
Patterson & Hennessy, © 2012, UCB]

2. Course Textbook and Outline
 Instructor: Dr. Nivine Güler
 Textbook(s):
 Computer Organization and Design: The
Hardware/Software Interface, 4th Edition, David
Patterson and John Hennessy, Morgan Kaufmann.
ISBN: 978-0-12-374493-7, 2012
 Topics covered:
 Computer Abstractions and Technology
 Instructions: Language of the Computer
 Arithmetic for Computers
 The processor
 Exploiting Memory Hierarchy

3. Grades
 Quizes 30%
 Chap 1, 2, 3
 Date to be announced
 Midterm Exam 30%
 Chap 4, Part of Chap 5
 Date to be announced
 Final 40%
 All material

4. The Computer Revolution
 Progress in computer technology
 Underpinned by Moore’s Law
 Makes ”science-fiction” applications
feasible
 Computers in automobiles
 Cell phones
 Human genome project
 World Wide Web
 Search Engines
 Computers are pervasive
Chapter
1
—
Computer
Abstractions
and
Technology

5. Classes of Computers
 Desktop computers
 General purpose, variety of software
 Subject to cost/performance tradeoff
 Server computers
 High capacity, performance, reliability
 Execute programs for multiusers
simultaneously and accessed by network.
 Embedded computers
 Hidden as components inside the systems
such as car, phone, video game, so on
 Designed to run one application integrated
with the hardware, and delivered as a single
system.
Chapter
1
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Computer
Abstractions
and
Technology

6. The Processor Market
Chapter
1
—
Computer
Abstractions
and
Technology

7. What You Will Learn
 How high level language programs, such
as C, are translated into the machine
language
 And how the hardware executes them?
 What is the hardware/software interface
 And how does the software instruct the
hardware to perform needed functions?
 What determines program performance
 And how it can be improved?
Chapter
1
—
Computer
Abstractions
and
Technology

8. What You Will Learn
 How can hardware designers improve
performance?
 What is parallel processing
 Switching from sequential processing to
parallel processing
Chapter
1
—
Computer
Abstractions
and
Technology

9. Understanding Performance
 Algorithm
 Determines number of operations executed
 Programming language, compiler, architecture
 Determine number of machine instructions executed
per operation
 Processor and memory system
 Determine how fast instructions are executed
 I/O system (including OS)
 Determines how fast I/O operations are executed
Chapter
1
—
Computer
Abstractions
and
Technology

10. Below Your Program
 Application software
 Written in high-level language
 System software
 Compiler: translates HLL code to
machine code
 Operating System: service code
 Handling input/output
 Managing memory and storage
 Scheduling tasks & sharing resources
 Hardware
 Processor, memory, I/O controllers
Chapter
1
—
Computer
Abstractions
and
Technology

11. Levels of Program Code
 High-level language
 Level of abstraction closer
to problem domain
 Provides for productivity
and portability
 Assembly language
 Textual representation of
instructions
 Hardware representation
 Binary digits (bits)
 Encoded instructions and
data
 Ex: 1000110010100000
Just tells the computer to add two numbers

12. Components of a Computer
 The five important components for all kinds of
computer are: Input, output, memory, datapath,
control( called processor)
 Input/output includes:
 User-interface devices
 Display, keyboard, mouse
 Storage devices
 Hard disk, CD/DVD, flash
 Network adapters
 For communicating with other computers
§1.3
Under
the
Covers
The BIG Picture

13. Anatomy of a Computer
LCD screen is
Output device
Keyboard
Input device
Mouse Input
device
Network
cable

14. Inside the Processor (CPU)
 Datapath: The component of the processor
that performs arithmetic operations
 Control: The component of the processor
that commands the datapath, memory, and
I/O devices according to the instructions of
the program
 Cache memory: consists of small and fast
SRAM memory for immediate access to
data

15. Hard drive
processor
Fan with cover
Spot for
memory DIMMs
Spot for battery Motherboard DVD drive

16. Inside the Processor
 AMD Barcelona: 4 processor cores

17. Abstractions
 Abstraction helps us deal with complexity
 Hide lower-level detail
 Instruction set architecture (ISA)
 The hardware/software interface :
encompasses all the information necessary to
write a machine language program
 Application binary interface
 The ISA combined with the system software
interface
 Implementation
 Hardware that obeys the architecture abstraction.

18. Defining Performance
 Which airplane has the best performance?
0 100 200 300 400 500
Douglas
DC-8-50
BAC/Sud
Concorde
Boeing 747
Boeing 777
Passenger Capacity
0 2000 4000 6000 8000 10000
Douglas DC-
8-50
BAC/Sud
Concorde
Boeing 747
Boeing 777
Cruising Range (miles)
0 500 1000 1500
Douglas
DC-8-50
BAC/Sud
Concorde
Boeing 747
Boeing 777
Cruising Speed (mph)
0 100000 200000 300000 400000
Douglas DC-
8-50
BAC/Sud
Concorde
Boeing 747
Boeing 777
Passengers x mph
§1.4
Performance

19. Response Time and Throughput
 Response time
 How long it takes to do a task
 Throughput
 Total work done per unit time
 e.g., tasks/transactions/… per hour
 How are response time and throughput affected
by
 Replacing the processor with a faster version?
 Adding more processors?
 We’ll focus on response time for now…

20. Relative Performance
 Define Performance = 1/Execution Time
 “X is n time faster than Y”
n

 X
Y
Y
X
time
Execution
time
Execution
e
Performanc
e
Performanc
 Example: time taken to run a program
 10s on A, 15s on B
 Execution TimeB / Execution TimeA
= 15s / 10s = 1.5
 So A is 1.5 times faster than B

21.  Please do the HOMEWORK!
Thank you all

Chapter 1 — Computer Abstractions and Technology — 37