OPERATING SISTEMS

1. Ştefan Stăncescu OPERATING SISTEMS Lecture 2 INTRODUCTION

2. MODEL TRANSMISSION / SYGNALS, CODES, LANGUAGES • Life evolution theory: • statistic experience accumulation, • acquired bydirect 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

3. 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

4. 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

5. MODEL TRANSMISSION / SYGNALS, CODES, LANGUAGES • Signaltransmission 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

6. MODEL TRANSMISSION / SYGNALS, CODES, LANGUAGES • Computer systems include structuresandmeans for • creation, memorization, transfer and deploymentof 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

7. Level structures of a computer system User applications Utility calls System utilities SO calls Operating systems BIOS calls Procedures Microinstructions Microprogram Micro commands H/W circuits

8. Level structures of a computer system User applications User applications, Solve a new problem, usually very complex with intellectual experience user experience and experience memorized in computer Elaborated by the application developers deliver solutions to the situations with difficulties, problems, that are source of unsatisfactory life to the users, improving users life

9. Level structures of a computer system 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.

10. Level structures of a computer system Operating systems Operating system coordinate H/Wcomponents (UC, MEM, IO, FS, etc.) în implementing of facilitiesof prepare, load and start in operation of programs, control evolution in processing detection 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

11. Level structures of a computer system Procedures Proceduresare 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.

12. Level structures of a computer system Microprogram Microprograms are lists, 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

13. Level structures of a computer system H/W circuits H/W circuits are persistent in timematerial 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 for logical hardware model.

14. Level structures of a computer system Computer systems, as complex systems, are organized between application reality with direct users and reality of materials in physical state, in a level structure, each level with appropriate 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

15. SOFTWARE ORGANIZATION Applications User management Business logic management System software System resources control Task management System utilities Data management Data communication Operating system System resources management

16. SYSTEM UTILITIES Assemblers convert automatically the program representation from man/machine understandable language assembly language to a binary form, loadable in memory and executable program object. Macroassemblers) next level for making assembly language more understandable, using templates as macroinstructions a template is a repetitive or frequent used list of assembly instructions. common used sequences are grouped, named and used as a newinstruction. as a user programmed instruction as new language element.

17. SYSTEM UTILITIES Compilers) automatic translators of sources files written in HLL to modules executable on computer H/W to be active in real machines. Macroprocessors with facilities added to an assembler/compiler offering new facilities from lists of existing ones direct acxcesible by new names or new accesses.

18. SYSTEM UTILITIES Linkers) link execuitable modules asamblate sau compilate separat în module compacte unitare. Încărcătoarele(loaders)de programe sau module executabile efectueazăoperaţii 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.

19. SYSTEM UTILITIES 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

20. SYSTEM UTILITIES Maşinile virtuale reprezină o expresie generalizată a soluţiei de prezentare spre dezvoltator şi utilizator a unei variante cunoscută şi standardizată a unui sistem de operare platforma 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, prietenos corespunzător experienţei deja câştigate de operatorul sau dezvoltatorul de aplicaţiecontrolată şi în viitor prin versiuni compatibile

21. SISTEME DE OPERARE Sistemele de operare formează un pachet 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 înamănunt si de a adapta solutia unei probleme la specificul fiecărei masini concrete pe careaceasta poate să rulezeîn viitor prin versiuni compatibile Sistemul de calcul devine o Maşina Virtuala

22. SISTEME DE OPERARE Gestiunea de procese Multiprocesare, multiprogramare, Procesare paralela Gestiunea de spatiu de memorie pentru procese Memorie fizica si virtuala Gestiunea de spatiu de IO pentru procese Drivere de dispozitive fizice si logice Gestiunea de fisiere Gestiunea spatiului memoriilor externe Sisteme de gestiune de fisiere Gestiunea de fiabilitate, protectie si securitate