OPERATING SISTEMS

Lecture 2

INTRODUCTION

Ştefan Stăncescu

1

MODEL TRANSMISSION / SYGNALS, CODES, LANGUAGES

Life evolution theory :

statistic experience accumulation,

acquired by direct experiences of active subjects,

in real world, building a solutions model

in the reality they live in.

 Acquired experience form a reality model

registered/memorized from a sign set

transmitted to other in the specie in contemporary

or over generations

by signal (biologically) set

2

MODEL TRANSMISSION / SYGNALS, CODES, LANGUAGES

Model transfer

has the privilege to give to end users

final optimal solution resulted from costly tries,

without any substantiual effort.

 Local models are transmitted

in time by

memory

in space by

signals

3

MODEL TRANSMISSION / SYGNALS, CODES, LANGUAGES

First signals for life experience transmission:

genetic biologic support

chemically by ADN memory

time multiplied in generations,

from individuals antecessors to successors

neuronal biologic support

memory, search, and association brain means

statistical studies or random solutions

individual life memory

empiric world models

prezintă avantajul de a le furniza destinatarilor

modelul final dedus din încercări,

scutind-i de efortul întregului proces de experimentare.

 Modelele locale se transmit

în timp prin

mecanisme de memorie şi

în spaţiu prin

semnale

4

MODEL TRANSMISSION / SYGNALS, CODES, LANGUAGES

Signal transmission systems between individuals:

support natural:

vizual - gestures

audio - ritual pseudo-artificial noises

- gutural produced noises, protolanguage

- limbaj vorbit spoken language

support artificial:

vizual - written language, pictural, spatial

electromagnetic – radio, TV, computers

prezintă avantajul de a le furniza destinatarilor

modelul final dedus din încercări,

scutind-i de efortul întregului proces de experimentare.

 Modelele locale se transmit

în timp prin

mecanisme de memorie şi

în spaţiu prin

semnale

5

MODEL TRANSMISSION / SYGNALS, CODES, LANGUAGES

Computer systems include structures and means for

creation, memorization, transfer and deployment of accumulated experience

Low complexity parts of intellectual processing

get out from human and externalize in machines

From well known models discovered by human beings

using only differential effort (only creative)

new solutions appears for new problems

Local models are transmitted

in time by memory mechanisms

in space by signaling

6

Level structures of a computer system

7

User applications

System utilities

Operating systems

Procedures

Microprogram

H/W circuits

Utility calls

SO calls

BIOS calls

Microinstructions

Micro commands

Level structures of a computer system

8

User applications

User applications, Solve a new problem, usually very complex

with intellectual experience user experience andexperience memorized in computer

Elaborated by the application developersdeliver solutions to the situations with

difficulties, problems, that are source of unsatisfactory life to the users,

improving users life

Level structures of a computer system

9

System utilities

System utilities assist application developers with facilities for improving their activities in design new solutions for direct users of applications, upgrading productivity and quality of the application.

asassemblers, interpreters, macroassembleres, macroprocesors, compilers, link editors, loaders, text editors, debuggers, libraries, etc.,

development media for special and general applications, system environments, configuration, administration, deployment, operating, testing, evaluating, certificating utilities, etc.

Level structures of a computer system

10

Operating systems

Operating system coordinateH/W components (UC, MEM, IO, FS, etc.)

în implementing of facilities ofprepare, load and start in operation of programs,control evolution in processingdetection and control unlinear evolution,combat errors and treat any exceptional or abnormal evolution.

virtualize H/W for multiprocessing standardize S/W and make interfaces/API user friendly

Level structures of a computer system

11

Procedures

Procedures are a mean to do elementary operations

regarding any computer ressource, in view to sustain an elementary functionality.Direct access on H/W by

microinstructions of microprocessors, in view to implement algorithms direct linked to some resource, with distinct link with direct resource control and management

emitting commands, receiving states for H/W specific circuits.

Level structures of a computer system

12

Microprogram

Microprograms arelists, sets of operations needed for

working microinstructions in microprocessors list of commends for H/W structures

included in uP, LSI, ASICS, NoC, internal commands in complex circuits, etc. furnish data structures in automatic processing

Level structures of a computer system

13

H/W circuits

H/W circuits are persistent in time material support that

memorize stabile intellectual experience, dedicated to make functional elementary operations,

used in flexible combinations for complex assemblies of operations

by direct access of physical support. This level is implemented by

technologies (analogic, digital combinatorial, sequential circuits) using

material physical laws forlogical hardware model.

Level structures of a computer system

14

Computer systems, as complex systems, are organizedbetween application reality with direct users andreality of materials in physical state,

in a level structure, each level withappropriate functionalities

to fulfill requested services. Only adjacent levels communicate ones with others through interface between them, by requests and granted services.Services are fulfilled integrally only in a single level by

level processes or “protocols”, implementing specialization of each level for

each abstract level of processing. Level structure and service communication between levels, standard level interfaces offer flexibility in complexity

SOFTWARE ORGANIZATION

15

Task management

Business logic management

User management

Data management

Data communication

System resources management

System resources controlSystem

utilities

Applications

Operating system

System software

SYSTEM UTILITIES

16

Assemblersconvert automatically the program representation

from man/machine understandable language assembly language

to a binary form, loadable in memory and executableprogram object.

Macroassemblers) next level for making assembly language more

understandable, using templates as macroinstructionsa template is a repetitive or frequent used list of

assembly instructions. common used sequences are grouped, named and

used as a new instruction.as a user programmed instruction as new language

element.

SYSTEM UTILITIES

17

Compilers) automatic translators of

sources files written in HLL to modules executable on computer H/Wto be active in real machines.

Macroprocessors with facilities added to an assembler/compiler

offering new facilities from lists of existing onesdirect acxcesible by new names or new accesses.

SYSTEM UTILITIES

18

Linkers) link execuitable modules

asamblate sau compilate separat în module compacte unitare.

Încărcătoarele (loaders) de programe sau module executabile efectuează operaţii de trecere

de la programe memorate şi gestionate de sisteme de gestiune de fişiere

în programe rezidente în memoria principală.Bibliotecile (libraries) de module preprocesate oferă

spre legare soluţii deja elaborate profesional pentru

probleme standard din domenii specializate.

SYSTEM UTILITIES

19

Depanatoarele (debuggers) şi analizoarele de performanţe (profilers) oferă

mijloace de control al modului obiect elaborat, în vederea obţinerii scopului urmărit

de programul elaborat.Mediile de dezvoltare pe domenii de aplicaţii

generale sau specializate, oferă metode şi mijloace de urmărire

a procesului de elaborare de programe pe parcursul întregului traseu al ciclului lor de

viaţă Mijloace de analiză de sistem şi unelte de modelare folosite în ingineria software, ca

mijloace de management al procesului de elaborare de aplicaţii

SYSTEM UTILITIES

20

Maşinile virtuale reprezină o expresie generalizată a soluţiei de prezentare spre dezvoltator şi utilizator a

unei variante cunoscută şi standardizată a unui

sistem de operareplatforma de lucru

privite ca mediu de lucru pentru aplicaţii. MV emuleaza mediul S/W si H/W al aplicaţiilor, care devine

un mediu cunoscut, stabil, prietenoscorespunzător experienţei deja câştigate de

operatorul sau dezvoltatorul de aplicaţiecontrolată şi în viitor prin

versiuni compatibile

SISTEME DE OPERARE

21

Sistemele de operare formează unpachet compact de programe de sistem cu scop comun

facilitarea utilizării sistemului de calcul, oferind un mediu de gestiune unitară pe

masini diferite. Elaboratorul de aplicatii este eliberat de sarcina complexă

de a construi în amănunt si de a adapta solutia unei probleme la specificul fiecărei masini concrete

pe carea ceasta poate să ruleze în viitor prin versiuni compatibile

Sistemul de calcul devine o Maşina Virtuala

SISTEME DE OPERARE

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Gestiunea de proceseMultiprocesare, multiprogramare, Procesare paralela

Gestiunea de spatiu de memorie pentru proceseMemorie fizica si virtuala

Gestiunea de spatiu de IO pentru proceseDrivere de dispozitive fizice si logice

Gestiunea de fisiereGestiunea spatiului memoriilor externeSisteme de gestiune de fisiere

Gestiunea de fiabilitate, protectie si securitate