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Development of the Interactive Package of Application Programs for Analytical Study of the Hierarchical Computer Systems
DEVELOPMENT OF THE I N T E R A C T I V E PACKAGE OF A P P L I C A T I O N PROGRAMS FOR A N A L Y T I C A L STUDY OF THE H I E R A R C H I C A L COMPUTER SYSTEMS
V.V.Pirogov, Corresponding Member of the Academy of Sciences of t h e Latvian SSR S .Ph.Gaistero~ , Engineer Yu.P.Petrov, Engineer I n s t i t u t e of E l e c t r o n i c s and Computing Technique of t h e Academy of Sciences of t h e Latvian SSR Riga, USSR ABSTRACT The paper coneiders t h e study of t h e comp u t e r systems (CS) by using a package of simulation programs (PSP). The s t r u c t u r e of tha package and implementation of t h e oonveraational mode of operation i n t h e course of simulation of t h e computer syst e m a r e described. The conversational mode of operation i s t r e a t e d as a means f o r studfing t h e computer system t o determine i t s optbum s t r u c t u r e . The des c r i p t i o n of t h e package contains t h e char a c t e r i s t i c of t h e a n a l y t i c a l and imit a t i v e models of a C6. The a n a l y t i c a l model i s designed f o r studying t h e three-level h i e r a r c h i c a l s t r u c t u r e s encompassing a broad c l a s s of CS; i t i s developed on t h e b a s i s of t h e queueing theory (QT) The i m i t a t i v e model i s designed f o r studging a CS with an a r b i t r a r y configur a t i o n having d i f f e r e n t f u n c t i o n a l algorithms, which c o n s i s t s of t h e following s t r u c t u r a l elements: a processor, a d a t a l i n k , an i n t e l l i g e n t tenrdnal, a terminal and a b u f f e r storage.
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Great a t t e n t h o n now i s being devoted t o t h e e f f o r t s aimed a t t h e development of t h e p r i n c i p l e s and procedures f o r designing a CS.This i s due t o t h e continu-
ous expansion of t h e spectrum of applicat i o n s of computer f a c i l i t i e s which r e s u l t s i n the development of a CS having various configurations t h a t range from simple onl i n e systems through the complex systems using a ramified d a t a communications network. Due t o t h e f a c t t h a t a CS includes a number of resources ( a s t o r a g e u n i t , CPU's, t e d n a l s , d a t a , colpmunication l i n e s ) t h e problem of studying t h e algorithms of t h e i r e f f e c t i v e u t i l i z a t i o n a r i s e s . Prom t h e point of view of t h e cont r o l t h e resources may be subdivided i n t o two groups. The computer resources are a t t r i b u t a b l e t o the f i r s t group, while t o t h e second t h e resources c o n t r o l l e d by a comgroup munications subsystem, i.e. communications l i n e s , a b u f f e r storage, terminals('). The resources belonging t o t h e f i r s t group a r e c o n t r o l l e d by t h e operating system of a computer; however, t h e c o n t r o l procedures f o r t h e resources belonging t o the second group a r e developed f o r each spec i f i c configuration of a CS. This r e s u l t s from: t h e multiple nature of p o s s i b l e structures; t h e multiple nature of t h e schemes of operation; t h e multiple nature of the algorithms f o r c o n t r o l l i n g t h e resources.
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rho multiple nature of possible structures i s detenrined by the type of the terminal connection t o the comunication l i n e (point-to-point connection, multidrop connection) and by the network topolo&g. The multiple nature of the schames of operation i s determined by the combinat i o n g f the resource u t i l i e a t i o n algorithm and the types of responses t o an interruption i n a CB. The multiple naturit of the resource cont r o l algorithms i s determined by the -routing of the mqueets , by servicing p r i o r i t i e s and by u t i l i e a t i o n of the buffe r storage. The mentioned m u l t i p l i c i t i e s determine i n t h e i r turn u t i l i e a t i o n of the resources and naturally depend on the stream of the system's i n c d n g requests and on the strear of t h e control infornation inglementing a p a r t i c u l a r scheme of operation i n a communication subsystem. A 1 1 t h e w factors require the developent of the adequate procedures f o r evaluating the quality of a C8. These procedums nust proride f o r the generation of various configurations and mastering the estimates f o r a broad spectrum of the ejstema qulity indice6 (ieer response tire, the caprcity, r e l i a b i l i t y , cost indices etc. 1. This problem may be solved by using different means of s i n i l a t i o n t simulation languages; simulation program packages; natural simulation means. Under d i f f e r e n t simulation conditions these m a n s ry be w d e i t h e r independently o r may corplement one another. The u m of the i n t e r a c t i v e package of eirulation prorides f o r the d a d r e d degree of adequacy of simulation, S e l d s the most effective s i m l a t i o n programs and does not require any special experience of a user i n the f i e l d of proc a n s . The description of t h e 08 simulation
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package i s given below. The package has been implemented on a WMG-ES computer system with the following distribution: the anawical model of a CS has been implemented on a WMG-?200B computer, while the imitative model on a E6-1020 computer. I n doing so the exchange of the r e s u l t s between both models i s possible, which yields the effective computing procedure. For e k p l e , the preparation of data used by the imitative model may be done by using several i n t e l l i g e n t terminals of t h e W M G type. Interactive analytical model of a hierarchical c m u t e r asatem (-1 The analytical model of the package i s being developed on t h e basis of a generalieed equivalent c i r c u i t of a 808 and has the f o m as &om i n Pig. 1. The description of the given c i r c u i t and the a l g o r i t h m f o r calculating the indices of a C8 are given i n (2). !he equivalent circ u i t s f o r d i f f e r e n t configurations of a EC0 naj be obtained by variating t h e nodes and the branches i n the generalleed equivalent c i r c u i t , as well as by repre-, aenting t h e r e a l structure of a OS i n t h e i o n of the composition of f r m n t s each of which corresponding t o the generalized equivalent c i r c u i t . To obtain the perfomance e e t i r a t e s f o r a HCS as consistent with the epecified generalized c i r c u i t , an interactive-anal y t i e a l model of a H08 (IAH HCS) hao been developed. The f e a t u r e s inherent i n an IAH ECS res u l t from: the use of the queueing t h e o r j (W)models; the modular programmed implementation of models; the i n t e r a c t i v e procedures f o r organiration and implementation of programs. Currently one u~ speak of two d i s t i n c t
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I n the course of simulation one may deterd i r e c t i o n s along which t h e methods of t h e mine approximately 30 i n d i c e s describing QT! f o r a n a l y t i c a l study of a CS a r e being d i f f e r e n t a s p e c t s of operation of a CS. used. The f i r s t onec3) i s aimed a t deterI f necessary, one may obtain weighted avmining t h e system response and u s e s a maerage i n d i c e s f o r t h e l e v e l s which a r e t r i x of a p r i o r i d i s t r i b u t i o n of stream used i n t h e i m i t a t i v e simulation of a CS i n t e n s i t i e s i n t h e d a t a l i n k s of a CS,the a s a source d a t a . response being determined on t h e b a s i s of a model with an i n f i n i t e source. The basI n t e r a c t i v e i m i t a t i v e model of t h e comi c d i f f i c u l t y of t h e given approach i s p u t e r system a s s o c i a t e d with c a l c u l a t i o n of the elements of an i n t e n s i t y matrix. The purpose of developing an i n t e r a c t i v e The second d i r e c t i o n involves t h e decomi m i t a t i v e model of a CS i s t o provide t h e p o s i t i o n of a 08 i n t o t h e elements vhich p o s s i b i l i t y of studying d i f f e r e n t resource are f u r t h e r analyzed by using the models c o n t r o l algorithms f o r a CS and t o use of t h e Cp. The b a e i c d i f f i c u l t y of t h e them a s a b a s i s f o r f u r t h e r i n v e s t i g a t i n g given d i r e c t i o n i s a s s o c i a t e d with t h e various schemes of operation of a CS. n e c e s s i t y t o meet t h e requirements of corTherefore an i m i t a t i v e model must meet t h e r e c t n e s s imposed on t h e system decomposir i g i d requirements a s t o i t s f l e x i b i l i t y . t i o n i n t o a number of t h e simplest c i r Usually i m i t a t i v e models of a CS describe c u i t s which would preserve t h e i n i t i a l one of t h e p o s s i b l e r e a l i z a t i o n s of a CS p a t t e r n of t h e stream d i s t r i b u t i o n . and t h e r e f o r e t h e i r p r a c t i c a l value i s To overcome t h e disadvantages of both l i m i t e d t o t h e given version. s t a t e d approaches a model of a three-levThe i n t e r a c t i v e i m i t a t i v e model (IU) i n e l centralized (hierarchical) structure question ( l ) i s more b e n e f i c i a l , i.e. it and an algoritiun t o c a l c u l a t e stream inencompasses a s u f f i c i e n t l y wide range of t e n s i t i e s i n such system are proposed c o n t r o l algorithms and schemes of operation which u t i l i z e : f o r a r b i t r a r y configurations of a CS; moreA. The models with a f i n i t e source: with over, the implementation of t h e model i n l i m i t a t i o n being imposed on time (waita package form makes i t possible t o dei n g f o r r e q u e s t s ) and on the amount of a b u f f e r storage of the computer; with s c r i b e the configuration and t h e c o n t r o l of a CS on t h e l e v e l of t h e i n p u t data. l i m i t a t i o n being imposed on t h e reThe i m i t a t i v e model i s based on t h e scheme sponse time; w i t h l i m i t a t i o n being imof events: t h e a r r i v a l of an incoming reposed on t h e b u f f e r s i z e ; without any quest from t h e request generator; t h e loadl i m i t a t i o n s (with waiting). ing; the r e l e a s e ; t h e malfunction; t h e end B. The QL!' models with an i n f i n i t e source: of servicing. with l i m i t a t i o n being imposed on t h e I n the course of simulation t h e r e s u l t s a r e response time and on t h e amount of a obtained a s t o t h e response time, t h e unb u f f e r storage of t h e computer; with loading of t h e elements of a CS and t h e l i m i t a t i o n being imposed on t h e rei d l e time of t h e elements due t o a malfuncsponse time; with l i m i t a t i o n being imt i o n . The r e s u l t on any index may be obposed on t h e b u f f e r s i z e ; without any t a i n e d i n the form of a histogram. limitations. The simulation i s p e d r m e d according t o Group A of models corresponds t o the two schemes: an averaged study and a comi n t e r a c t i v e mode of operation of a C S , p l e t e study. I n the f i r s t case the r e s u l t s while group B - t o the batch mode.
being obtained i n the process of simulat i o n a r e correlated according t o the types of the elements being investigated, while i n the second case the additional r e s u l t s on each element of a CS are obtained i n the end of simulation. s t Z X l ~ b eof the ~ b ~ l a t i oDrORX?am n ~ackis2 A complete package of simulation programs (PSP) consists of the PSP X U package realizable on a WMG-2200B computer ( o r a similar minicomputer) and the PSP IIM package realizable on a ES computer (la-1020 with DOS E6). The PSP has a complex modular structure which i n t e r a c t s with the operating system of the computer t o provide the generation of a processing progrem and a number of functions r e l a t e d t o the maintenance of the package. The modules incorporated i n the package a r e distributed i n t o the following groups: functional modules which perform the t a r g e t functions of the system being developed; supplementary modules which allow t o form d i f f e r e n t modes (interactive promame, programs t o operate with lib r a r i e s etc.), monitoring the system's protection against destruction, f i l e recording; these modules provide f o r the stable operation of functional modules; information modules which are the input and the output f i l e s a s well a s the intermediate data f i l e s ; control modules which make up the package scheduler (monitor); package generation modules which provide f o r the package loading i n t o the CS together with the control t r a n s f e r t o the package scheduler. The package control i s made by the system scheduler "GUD0" by using model schedu l e r s GUDl,...,GUDN, whose program implementation is made i n the form of over-
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lapping phases. Each model scheduler cont r o l s i n i t s turn the s e t of jobs and i s a root phase r e l a t i v e t o these jobs, i.6. the scheduler and the s e t of jobs with the models~makeup an overlay structure. I n addition t o the operation with model schedulers the systems scheduler's funct i o n s include creation of t h e l i b r a r y and the information f i l e maintenance f o r the library' operation. The feature of the PSP l i e s i n the f a c t t h a t creation and updating of the l i b r a r i e s encompass several t e n s of modules and t h e given modificatione a r e being recorded i n the source, the object and the absolute module librar i e s . To solve the given problem under DOS/ES the package modules generate on an external medium a job stream t o perform different actions with the-package programs.
The developed generalized package of simul a t i o n programs which includes the P6P I A M and the PSP IIM makes it possible t o simul a t e an extensive spectrum of C S configurations. It does not impose any s t r i c t requirements on the l e v e l of user preparation.
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mpOF0B B.,&TpOB Y).,I'agc~epoB C. haraTwecKoe ~ o ~ ~ B HpW ~ Eo T ~ J~I S - e HHX CHCTeM. Cd. " M O ~ & U E ~ P O B ~ I ~ C.XCiubix B~ cac~en", mn. 4."3mia~ae", *a, 1975.
3. K n e a p o ~JI. k m y m m m o m i e cem (CTOxacmnecme n m o m a wecoodnlemitill. wHagKa", blocmi, 1970.
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V.V.Pirogov, Corresponding Member of the Academy of Sciences of t h e Latvian SSR S .Ph.Gaistero~ , Engineer Yu.P.Petrov, Engineer I n s t i t u t e of E l e c t r o n i c s and Computing Technique of t h e Academy of Sciences of t h e Latvian SSR Riga, USSR ABSTRACT The paper coneiders t h e study of t h e comp u t e r systems (CS) by using a package of simulation programs (PSP). The s t r u c t u r e of tha package and implementation of t h e oonveraational mode of operation i n t h e course of simulation of t h e computer syst e m a r e described. The conversational mode of operation i s t r e a t e d as a means f o r studfing t h e computer system t o determine i t s optbum s t r u c t u r e . The des c r i p t i o n of t h e package contains t h e char a c t e r i s t i c of t h e a n a l y t i c a l and imit a t i v e models of a C6. The a n a l y t i c a l model i s designed f o r studying t h e three-level h i e r a r c h i c a l s t r u c t u r e s encompassing a broad c l a s s of CS; i t i s developed on t h e b a s i s of t h e queueing theory (QT) The i m i t a t i v e model i s designed f o r studging a CS with an a r b i t r a r y configur a t i o n having d i f f e r e n t f u n c t i o n a l algorithms, which c o n s i s t s of t h e following s t r u c t u r a l elements: a processor, a d a t a l i n k , an i n t e l l i g e n t tenrdnal, a terminal and a b u f f e r storage.
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Great a t t e n t h o n now i s being devoted t o t h e e f f o r t s aimed a t t h e development of t h e p r i n c i p l e s and procedures f o r designing a CS.This i s due t o t h e continu-
ous expansion of t h e spectrum of applicat i o n s of computer f a c i l i t i e s which r e s u l t s i n the development of a CS having various configurations t h a t range from simple onl i n e systems through the complex systems using a ramified d a t a communications network. Due t o t h e f a c t t h a t a CS includes a number of resources ( a s t o r a g e u n i t , CPU's, t e d n a l s , d a t a , colpmunication l i n e s ) t h e problem of studying t h e algorithms of t h e i r e f f e c t i v e u t i l i z a t i o n a r i s e s . Prom t h e point of view of t h e cont r o l t h e resources may be subdivided i n t o two groups. The computer resources are a t t r i b u t a b l e t o the f i r s t group, while t o t h e second t h e resources c o n t r o l l e d by a comgroup munications subsystem, i.e. communications l i n e s , a b u f f e r storage, terminals('). The resources belonging t o t h e f i r s t group a r e c o n t r o l l e d by t h e operating system of a computer; however, t h e c o n t r o l procedures f o r t h e resources belonging t o the second group a r e developed f o r each spec i f i c configuration of a CS. This r e s u l t s from: t h e multiple nature of p o s s i b l e structures; t h e multiple nature of t h e schemes of operation; t h e multiple nature of the algorithms f o r c o n t r o l l i n g t h e resources.
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rho multiple nature of possible structures i s detenrined by the type of the terminal connection t o the comunication l i n e (point-to-point connection, multidrop connection) and by the network topolo&g. The multiple nature of the schames of operation i s determined by the combinat i o n g f the resource u t i l i e a t i o n algorithm and the types of responses t o an interruption i n a CB. The multiple naturit of the resource cont r o l algorithms i s determined by the -routing of the mqueets , by servicing p r i o r i t i e s and by u t i l i e a t i o n of the buffe r storage. The mentioned m u l t i p l i c i t i e s determine i n t h e i r turn u t i l i e a t i o n of the resources and naturally depend on the stream of the system's i n c d n g requests and on the strear of t h e control infornation inglementing a p a r t i c u l a r scheme of operation i n a communication subsystem. A 1 1 t h e w factors require the developent of the adequate procedures f o r evaluating the quality of a C8. These procedums nust proride f o r the generation of various configurations and mastering the estimates f o r a broad spectrum of the ejstema qulity indice6 (ieer response tire, the caprcity, r e l i a b i l i t y , cost indices etc. 1. This problem may be solved by using different means of s i n i l a t i o n t simulation languages; simulation program packages; natural simulation means. Under d i f f e r e n t simulation conditions these m a n s ry be w d e i t h e r independently o r may corplement one another. The u m of the i n t e r a c t i v e package of eirulation prorides f o r the d a d r e d degree of adequacy of simulation, S e l d s the most effective s i m l a t i o n programs and does not require any special experience of a user i n the f i e l d of proc a n s . The description of t h e 08 simulation
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package i s given below. The package has been implemented on a WMG-ES computer system with the following distribution: the anawical model of a CS has been implemented on a WMG-?200B computer, while the imitative model on a E6-1020 computer. I n doing so the exchange of the r e s u l t s between both models i s possible, which yields the effective computing procedure. For e k p l e , the preparation of data used by the imitative model may be done by using several i n t e l l i g e n t terminals of t h e W M G type. Interactive analytical model of a hierarchical c m u t e r asatem (-1 The analytical model of the package i s being developed on t h e basis of a generalieed equivalent c i r c u i t of a 808 and has the f o m as &om i n Pig. 1. The description of the given c i r c u i t and the a l g o r i t h m f o r calculating the indices of a C8 are given i n (2). !he equivalent circ u i t s f o r d i f f e r e n t configurations of a EC0 naj be obtained by variating t h e nodes and the branches i n the generalleed equivalent c i r c u i t , as well as by repre-, aenting t h e r e a l structure of a OS i n t h e i o n of the composition of f r m n t s each of which corresponding t o the generalized equivalent c i r c u i t . To obtain the perfomance e e t i r a t e s f o r a HCS as consistent with the epecified generalized c i r c u i t , an interactive-anal y t i e a l model of a H08 (IAH HCS) hao been developed. The f e a t u r e s inherent i n an IAH ECS res u l t from: the use of the queueing t h e o r j (W)models; the modular programmed implementation of models; the i n t e r a c t i v e procedures f o r organiration and implementation of programs. Currently one u~ speak of two d i s t i n c t
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I n the course of simulation one may deterd i r e c t i o n s along which t h e methods of t h e mine approximately 30 i n d i c e s describing QT! f o r a n a l y t i c a l study of a CS a r e being d i f f e r e n t a s p e c t s of operation of a CS. used. The f i r s t onec3) i s aimed a t deterI f necessary, one may obtain weighted avmining t h e system response and u s e s a maerage i n d i c e s f o r t h e l e v e l s which a r e t r i x of a p r i o r i d i s t r i b u t i o n of stream used i n t h e i m i t a t i v e simulation of a CS i n t e n s i t i e s i n t h e d a t a l i n k s of a CS,the a s a source d a t a . response being determined on t h e b a s i s of a model with an i n f i n i t e source. The basI n t e r a c t i v e i m i t a t i v e model of t h e comi c d i f f i c u l t y of t h e given approach i s p u t e r system a s s o c i a t e d with c a l c u l a t i o n of the elements of an i n t e n s i t y matrix. The purpose of developing an i n t e r a c t i v e The second d i r e c t i o n involves t h e decomi m i t a t i v e model of a CS i s t o provide t h e p o s i t i o n of a 08 i n t o t h e elements vhich p o s s i b i l i t y of studying d i f f e r e n t resource are f u r t h e r analyzed by using the models c o n t r o l algorithms f o r a CS and t o use of t h e Cp. The b a e i c d i f f i c u l t y of t h e them a s a b a s i s f o r f u r t h e r i n v e s t i g a t i n g given d i r e c t i o n i s a s s o c i a t e d with t h e various schemes of operation of a CS. n e c e s s i t y t o meet t h e requirements of corTherefore an i m i t a t i v e model must meet t h e r e c t n e s s imposed on t h e system decomposir i g i d requirements a s t o i t s f l e x i b i l i t y . t i o n i n t o a number of t h e simplest c i r Usually i m i t a t i v e models of a CS describe c u i t s which would preserve t h e i n i t i a l one of t h e p o s s i b l e r e a l i z a t i o n s of a CS p a t t e r n of t h e stream d i s t r i b u t i o n . and t h e r e f o r e t h e i r p r a c t i c a l value i s To overcome t h e disadvantages of both l i m i t e d t o t h e given version. s t a t e d approaches a model of a three-levThe i n t e r a c t i v e i m i t a t i v e model (IU) i n e l centralized (hierarchical) structure question ( l ) i s more b e n e f i c i a l , i.e. it and an algoritiun t o c a l c u l a t e stream inencompasses a s u f f i c i e n t l y wide range of t e n s i t i e s i n such system are proposed c o n t r o l algorithms and schemes of operation which u t i l i z e : f o r a r b i t r a r y configurations of a CS; moreA. The models with a f i n i t e source: with over, the implementation of t h e model i n l i m i t a t i o n being imposed on time (waita package form makes i t possible t o dei n g f o r r e q u e s t s ) and on the amount of a b u f f e r storage of the computer; with s c r i b e the configuration and t h e c o n t r o l of a CS on t h e l e v e l of t h e i n p u t data. l i m i t a t i o n being imposed on t h e reThe i m i t a t i v e model i s based on t h e scheme sponse time; w i t h l i m i t a t i o n being imof events: t h e a r r i v a l of an incoming reposed on t h e b u f f e r s i z e ; without any quest from t h e request generator; t h e loadl i m i t a t i o n s (with waiting). ing; the r e l e a s e ; t h e malfunction; t h e end B. The QL!' models with an i n f i n i t e source: of servicing. with l i m i t a t i o n being imposed on t h e I n the course of simulation t h e r e s u l t s a r e response time and on t h e amount of a obtained a s t o t h e response time, t h e unb u f f e r storage of t h e computer; with loading of t h e elements of a CS and t h e l i m i t a t i o n being imposed on t h e rei d l e time of t h e elements due t o a malfuncsponse time; with l i m i t a t i o n being imt i o n . The r e s u l t on any index may be obposed on t h e b u f f e r s i z e ; without any t a i n e d i n the form of a histogram. limitations. The simulation i s p e d r m e d according t o Group A of models corresponds t o the two schemes: an averaged study and a comi n t e r a c t i v e mode of operation of a C S , p l e t e study. I n the f i r s t case the r e s u l t s while group B - t o the batch mode.
being obtained i n the process of simulat i o n a r e correlated according t o the types of the elements being investigated, while i n the second case the additional r e s u l t s on each element of a CS are obtained i n the end of simulation. s t Z X l ~ b eof the ~ b ~ l a t i oDrORX?am n ~ackis2 A complete package of simulation programs (PSP) consists of the PSP X U package realizable on a WMG-2200B computer ( o r a similar minicomputer) and the PSP IIM package realizable on a ES computer (la-1020 with DOS E6). The PSP has a complex modular structure which i n t e r a c t s with the operating system of the computer t o provide the generation of a processing progrem and a number of functions r e l a t e d t o the maintenance of the package. The modules incorporated i n the package a r e distributed i n t o the following groups: functional modules which perform the t a r g e t functions of the system being developed; supplementary modules which allow t o form d i f f e r e n t modes (interactive promame, programs t o operate with lib r a r i e s etc.), monitoring the system's protection against destruction, f i l e recording; these modules provide f o r the stable operation of functional modules; information modules which are the input and the output f i l e s a s well a s the intermediate data f i l e s ; control modules which make up the package scheduler (monitor); package generation modules which provide f o r the package loading i n t o the CS together with the control t r a n s f e r t o the package scheduler. The package control i s made by the system scheduler "GUD0" by using model schedu l e r s GUDl,...,GUDN, whose program implementation is made i n the form of over-
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lapping phases. Each model scheduler cont r o l s i n i t s turn the s e t of jobs and i s a root phase r e l a t i v e t o these jobs, i.6. the scheduler and the s e t of jobs with the models~makeup an overlay structure. I n addition t o the operation with model schedulers the systems scheduler's funct i o n s include creation of t h e l i b r a r y and the information f i l e maintenance f o r the library' operation. The feature of the PSP l i e s i n the f a c t t h a t creation and updating of the l i b r a r i e s encompass several t e n s of modules and t h e given modificatione a r e being recorded i n the source, the object and the absolute module librar i e s . To solve the given problem under DOS/ES the package modules generate on an external medium a job stream t o perform different actions with the-package programs.
The developed generalized package of simul a t i o n programs which includes the P6P I A M and the PSP IIM makes it possible t o simul a t e an extensive spectrum of C S configurations. It does not impose any s t r i c t requirements on the l e v e l of user preparation.
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mpOF0B B.,&TpOB Y).,I'agc~epoB C. haraTwecKoe ~ o ~ ~ B HpW ~ Eo T ~ J~I S - e HHX CHCTeM. Cd. " M O ~ & U E ~ P O B ~ I ~ C.XCiubix B~ cac~en", mn. 4."3mia~ae", *a, 1975.
3. K n e a p o ~JI. k m y m m m o m i e cem (CTOxacmnecme n m o m a wecoodnlemitill. wHagKa", blocmi, 1970.
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