Basic Concepts

1

Basic Concepts http://www.pds.ewi.tudelft.nl/~iosup/Courses/2011_ti1400_2.ppt

2

TU-DelftTI1400/11-PDS

2

Making functions

time

A,B Y

delay

A

BYADD

nand gates

3


3

Functional Units

• It would be very uneconomical to construct separate combinatorial circuits for every function needed

• Hence, functional units are parameterized

• A specific function is activated by a special control string F

4


4

Arithmetic and Logic Unit

F add subtract compare or

f1 f0 0 0 0 1 1 0 1 1

A

BYF

F

F

A B

YF

5


5

Repeated operations

• Y : = Y + Bi, i=1..n• Repeated addition requires feedback• Cannot be done without intermediate

storage of results

BYF

F

6


6

Registers

BYF

F = storage element

7


Outline

1. Programmable Devices2. A History of Computer Architectures

1. Pre-History (to 1930s)2. 1st Generation: Electro-Mechanical (1930s-

1950s)3. 2nd Generation: Transistors (1955—1975)4. 3rd Generation: Microprocessors (1960s—today)5. 4th Generation: Multi-Computing (1969—today)

8


Memory Organization

• In most computers bitstrings are grouped in strings of 8 bit, called byte

• A word consists of a number of bytes• Is dependent on the type of computer

9


Main memory

• Organized as a linear list of registers or memory locations

• Each memory location has a separate address, usually starting from 0 onwards

10


Memory Organization

• A main memory with a total number of bits can be organized in various ways depending on:- the size of the smallest addressable word- the number of memory locations

• For example: memory contains 4096 bits- 512 bytes of 8 bit- 256 words of 16 bit- 128 words of 32 bits

11

Question

Why is the memory size usually a power of 2 ?

12


Programmable devices

• A program is a sequence of operations on a stream of operands

• Operations are functions, like F• Operands are data elements (e.g.

numbers)

13


Programmable device

2,1 3ProgrammableDevice

input stream output stream

programREAD(X)READ(Y)ADD(X,Y,Z)WRITE(Z)

• READ(X) means read next input value from input stream and store it internally as variable X

• WRITE(X) means put value in variable X on output stream• ADD(X,Y,Z) means assign value of X+Y to Z

14


Program sequencing• We need a mechanism to execute a

program- FETCH operation that reads next instruction- EXECUTE operation that performs specified

operation on operands• And....repeat it forever:

forever loop FETCH EXECUTEend loop

15


FETCH

READ(X)READ(Y)ADD(X,Y,Z)WRITE(Z)

X: 1Y: 2Z: ?? • •

TEMP_A:TEMP_B:RESULT:

IR: ADD(X,Y,Z)

PC:

arithmeticunit

Central Processing Unit

Harvard Architecture

16


EXECUTE


X: 1Y: 2Z: 3 • •

TEMP_A: 1TEMP_B: 2RESULT: 3

IR: ADD(X,Y,Z)

PC:= PC+1

arithmeticunit


Harvard Architecture

17

Question

How can the previous scheme be simplified ?

18


Von Neumann“Conceptually we have [...] two different forms of

memory: storage of numbers and storage of orders. If, however, the orders to the machine are reduced to a numerical code and if the machine can in some fashion distinguish a number from an order, the memory organ can be used to store both numbers and orders”

Burks, Goldstine, von Neumann “Preliminary discussion of the logical design of an electronic computing instrument”

19


Von Neumann Architecture


X: 1Y: 2Z: 3 • •

TEMP_A: TEMP_B: RESULT:

IR:

PC:

arithmeticunit


CONTROL

Memory

Input

Output

20


High Level Programming• Simple program: P:= M*N• Simplify program: P:= M+ .... + M (N times)• Can be expressed as:

R:=0;P:=0;while R<N loop P:=P+M; R:=R+1;end loop

21


Three levels of instructions

fetch/executeimplementation

program executionin hardware

high level programminglanguage

program expressed in ahigh-level language

translation

instruction set program expressed as a series of instructions

direct implementation

22


Operating system

main storeprocessor

diskskeyboard

storagemanager

keyboardhandler

processorscheduler

diskhandler

service programs

hardware

23


Virtual, Multi-layer Machineoperating system interface

service programs

programming language

instruction set

language translator

hardware

24


Outline




25


History• Improving speed of operation by

mechanical means- bicycle -> 5 times faster than walking (1 order

of magnitude)- airplane -> 200 times faster than walking (2

o.m.)

• Multiplication of two 9 figure numbers- by hand: 10 minutes- by computer: 100 nanosec (10 o.m.)

• Predicting weather? (accurately)

26


Invention

• Computer is not a single invention• Ideas from mathematics, physics,

mechanical and electrical engineering• Development of calculation machines

strated in 17-th Century:- Pascal: two (+,-) operation machine in

1642- Leibnitz: four operation machine in 1671

27


Calculators

• Machines of Pascal and Leibnitz were mechanical calculators

• Could do single operation at a time• Lead to electronic calculators in 1975

28


Programmable devices

• Devices that could execute a program existed in different areas:

• Mechanical Music Instruments- Bagdad, 9-th Century- Carillons

• Chess / Mechanical Turk (1770)?• Punch Cards for weaving machines

- Jaquard (end 18-th Century)

29


The Jaquard Loom (actually, Head)

http://en.wikipedia.org/wiki/File:Swedish_weaving.jpg

30


Difference Engine

• Invented by Johann Helfrich von Müller (1786)• Used by Charles Babbage (1822)

31


Charles Babbage

• Inspired by Jaquard mechanism• Designed “Analytical Engine” (1837)• Never completed• First machine with stored

program concept (calculations+order sequences)

32


Herman Hollerith

• Punch Cards for processing census data of the 1890 census in US

• Great success• Founded Tabulating Machine Company

(1889). Later became IBM.

33


Mathematical Influence

• George Boole (1854) showed that logic could be reduced to a simple algebraic system

• Work remained a curiosity until rediscovered by Whitehead and Russell in Principia Mathematica (1910-1913)

• Then, formal logic developed resulting in Gödel and the work of Alan Turing

34


Analog Computers

• Analog computers predated digital computers- Slide rule- Mechanical integrators used in differential

analyzers (Vannevar Bush, 1931)• First systems that enabled significant

reduction of calculation times

35


Mechanical analog computer

36


Outline




37


Electro-Mechanical DevicesASCC• 1937-1944, Howard Aiken builds the Automatic

Sequence Controlled Calculator (ASCC), an electro-mechanical device - First general-purpose digital computer- 750,000 components, 5 tons

• Goal: 100 times faster than by hand • Reality: 3-5 times faster

“Only six electronic digital computers would be

required to satisfy the computing needs of the entire United States.”

38


Electro-Mechanical DevicesENIAC• 1943-1947, John Mauchly and John Presper

Eckert started building the Electronic Numerical Integrator and Calculator (ENIAC). - First all-electronic computer- 18,000 tubes, 1,500 relays, 150 kilowatt dissipation- Large office space

39


Electro-Mechanical DevicesProblems with ENIAC

• Each time switched on: 10 tubes failed• Difficult to program• Not very flexible• Technologically too complex• Decentralized control• Too small a memory

40


Electro-Mechanical DevicesEDVAC• Problems analyzed by John von

Neumann• Proposed new design: Electronic

Discrete Variable Automatic Computer (EDVAC)

• Basis so called Von Neumann Architecture

Memory

CPU

I O

41


Harvard or von Neumann Architecture?• Harvard Architecture

- Separate Instruction and Data memories (word size)- Separate memory-CPU pathways

• Von Neumann Architecture- Single Instruction and Data memory- Separate memory-CPU pathways

• Answer: Modified Harvard Architecture (hybrid)- Separate CPU (L1) caches for Instruction and Data- Unified memory hierarchy outside L1

42


Outline


1. Pre-History (to 1930s)2. 1st Generation: Electro-Mechanical (1930s-1950s)3. 2nd Generation: Transistors (1955—1975)4. 3rd Generation: Microprocessors (1960s—

today)5. 4th Generation: Multi-Computing (1969—today)

43


Transistors (1955—1975) and Microprocessors (1960s—today)

• Transistors- Reliable- Less power- Smaller

• U. Manchester (1953)• PDP-1

- 10 us / arith. instruction

• Integrated Circuits- Enabled small, low-

costmicroprocessors

• MOS Tech (ATARI)• Commodore PET• Apple & Apple ][• Current technology

44


Outline


1. Pre-History (to 1930s)2. 1st Generation: Electro-Mechanical (1930s-1950s)3. 2nd Generation: Transistors (1955—1975)4. 3rd Generation: Microprocessors (1960s—today)5. 4th Generation: Multi-Computing (1969—

today)

45


The Internet: Early History• 1965-1969 ARPANET

- Leonard Kleinrock developsthe Queueing Theory (theoretical properties of the Internet)

- 4 computers at UC Santa BarbaraUC Los AngelesStanford Research Inst.U of Utah

• 1972 ARPANET public + Email• 1974 TCP/IP at Stanford• 1982 ARPANET + TCP/IP = the (early) Internet

Drawing by Alex McKenzie, Dec 1969

46


The Internet Today

net, ca, uscom, orgmil, gov, eduasiade, uk, it, fr, plbr, kr, nlunknown

Source: http://www.opte.org/maps/

http://www.opte.org/maps/

47


Internet-Based Applications

48


ResearchABILENE: Backbone Research Network• Test: Land Speed Record

• ~ 7 Gb/s in single TCP stream from Geneva to Caltech

Source: MonALISA monitoring framework, 2005

49


ResearchGrid Computing

• The Grid = integration of computers as day-to-day computing utility, similar to phone, water, and electricity

- Economy of scale: better service at lower cost- Large-scale reality: operational overhead, functionality

(robustness + manageability), real heterogeneity

• Primary users- E-Science: high-energy physics, earth sciences, bioinformatics- Industry: financial services, search engines (Google)

Just plug in the computing grid and get your results

50


ResearchGrids: Vision vs. Reality• Many grids deployed, but not The Grid• Cloud computing?

Basic Concepts

Documents

Transcript of Basic Concepts