SU1481790A1 - Queueing system simulator - Google Patents

Abstract

The invention relates to specialized computer facilities and is intended to simulate the process of servicing a quotation. The purpose of the invention is to expand the functionality of the device by simulating a service interruption in each of the phases of a two-phase queuing system (QS). THE PURPOSE IS PROVIDED IN THE INTRODUCTION TO THE DEVICE OF THE UNIT OF THE DISTRIBUTION OF THE PHASES OF SERVICE, TWO ELEMENTS AND AND NOT two elements OR. The essence of the invention is to achieve the possibility of modeling the process of servicing applications for two models of QS: in a two-channel QS with failures with stochastic distribution of bills between service channels and in a single-channel two-phase QS servants servos; in two service phases, and the possibility of waiting for a second phase service. 2 Il.

Description

The invention relates to specialized computer systems and is intended to simulate the process of servicing a quotation.

The purpose of the invention is to expand the functionality of the device by simulating a service interruption in each of the phases of a two-phase service system.

Fig. 1 shows a functional diagram of a device for simulating queuing systems; Fig. 2 shows an embodiment of a block for allocating service phases.

The device contains a trigger 1 control, trigger 2 mode selection,

service phase distribution unit 3, 4 clock pulse generator, 5 random pulse generator, first 6, second 7, fifth 8, third 9, twelfth 10, fourteenth 11, eighth 12, ninth 13 and fourth 14 AND elements, first OR element 15, the third element AND-NOT 16, the fourth element AND-NOT 17, the second element OR 18, the second 19 and the first 20 reverse pulse counters, the sixth element And 21, the fourth 22 and the third 23 elements OR, the seventh element And 24, the first 25 and the second 26 triggers, the sixth 27 and the seventh 28 elements OR, the first 29 and second 30 drivers

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WITH

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pulses, the third reversible counter 31 pulses, the first element AND-NOT 32, the fifth element OR 33, the second element AND-NOT 34, the thirteenth element And 35, the eighth element OR 36, the tenth 37 and the eleventh 38 elements And, information input 39 , inputs 40 and 41 trigger 2.

The service phase distribution unit 3 comprises a counter 42, a decoder 43, a dial pad 44, and an OR element 45.

The invention consists in the possibility of achieving a simulation of the service process in two models of QS - a two-channel QS with failures with stochastic distribution of the gap between the service channels and a single-channel two-phase QS with the distribution of time intervals of the service phases and the possibility of waiting for the service of the second phase. Thus, in the second mode of operation of the device, each application enters the service in a single-channel QS. Moreover, applications in it must go through two phases of service, each of which is allocated a certain interval of service times. Two applications can be in service at the same time, but they are serviced alternately: the application that is serviced by the first phase is served first, and then the application that is serviced by the second phase is served and again in the same sequence. The intervals of the service phases follow alternately, changing each other.

If in dynamics we consider the process of servicing a stock in this mode, then it will be as follows. For example, for example, some service is received for service. If the device is in the time interval of the first phase, then this application is directly serviced; if the device is in the time interval of the second phase, then the application waits for the time of the first service phase, with the onset of which it immediately begins to be serviced. If the service of the application ends before the end of the time interval of the first service phase, it goes on to service the second phase and waits for the time of the onset of this service phase. If about 7904

If this service is not completed until the end of the time interval of the first service phase, then its service is interrupted for the time interval of the second service phase, and the continuation and end of service occurs at the next time intervals of the first service phase. After

If this application for servicing the second phase is transferred, the next application for servicing becomes the servicing of the first phase, where it is served according to the described algorithm.

5 If the application that has passed the first phase of the service goes on to service the second phase, but the previous application is in service of the second phase, then the application requiring the service of the second phase becomes a queue designed for the n-1 place, where waits for service of the second phase until the moment of release of the servicing device of the second phase. Servicing a quota in the second phase of servicing is similar to servicing a quota in the first phase of servicing. Those applications that go to the service when the servicing device of the first phase of the service is occupied receive a denial of service. When applications waiting for the second phase service, all queue locations, the acceptance of the next application for the first phase service is terminated. Thus, the system can maximally contain a PI application, of which one is in the service of the first phase, one is in

Q servicing the second phase; Clause-1 of the wok waiting for second phase service is in the queue.

The device can operate in two modes: as a two-channel QS with failures and as a single-channel two-phase QS with time distribution of the service phase intervals and the possibility of waiting for service of the second phase.

Service channels or servicing devices for the first SMO medal are triggers 25 and 26. They simulate the servicing devices of the first and second service phases for the second model of the MSS. Each of the triggers can be in one of two states: either imitate the service (channel busy) or be free.

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The presence of high unit potentials at the direct outputs of the flip-flops 25 and 26 indicates the idle state of the corresponding service channel for the first model or the service device of the corresponding service cycle for the second model.

The requirements (requirements) are short duration pulses arriving at the device information input 39. The applications are accepted for servicing in the period of time when at least one channel is free in the first mode and if the trigger 25 is in the one state and there is no need to read the required time interval for the application in the first service cycle, i.e. at the output of the element OR 22, a low zero potential is formed in the second mode of operation of the device.

In the second mode of operation, the devices model the discipline of, as it were, the servicing of applications that are serviced by the first and second cycle, if their required service interval was interrupted by the end of the time interval allocated for one or the other service cycle. At the same time, using a reversible counter 19 or 20, a time interval equal to the additional servicing time of the application is memorized. After the simulation of service in the trigger 25 has been completed, the next service phase will be received only after a time interval whose value is stored in the reversible counter 19. Similarly, the second order directly to the service of the second phase on trigger 26 is received after the end of the service simulation of the previous application in trigger 26 and through the time interval The value of which is stored in the reversible counter 20. The determination of the indicated time intervals is carried out by counting the number of pulse periods T following that generated by the 4 clock pulse generator. The formers 29 and 30 produce pulses of short duration during a differential at zero unit potential, which is given to their inputs. Duration

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the pulses produced by the formers 29 and 30 imitate the time of transfer of applications from one service phase to another or from a queue to service the second phase.

A reversible counter 31 records the number of requests that are being serviced and are waiting for a service — 10 or the second cycle. If reversible

Since the counter 31 is in its limit state, the next requests for servicing the first cycle are not accepted.

15 Triggers 25 and 26 go to the unit state at the time of the drops to the unit zero potentials acting on their direct inputs, and to the zero one - on the contrary, at the time of the transitions to the zero unit potentials acting on their inverse inputs. The reversible counter 31 changes its state under the action of the drops of unit potentials to zero, acting on its summing or subtracting outputs.

The service cycle distribution unit 3 (FIG. 2) generates a pulse train with a different duty cycle, which is possible

change with the help of jumpers of keypad 44. The unit potential at the output of unit 3 corresponds to the distribution of the time interval for the first service phase, and the zero potential for the second service phase. Using the counter 42 and the decoder 43, changing their state under the influence of pulses from the generator 4, the inputs of the pad 44 are sequentially excited. Using jumpers closing the inputs of the pad 44 in a certain predetermined sequence, the required distribution of time intervals for the maintenance cycles . The element OR 45, combining the outputs of keypad 44, forms at its output a specified distribution of time intervals of service cycles in the sequential code.

The device works as follows.

Suppose the positive logic of the device. Consider the operation of the device in the first mode. This means that the first input 40 of the installation of the operating mode of the device received a signal at the input of the terminal 35

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45

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Hera 2 selects the operating mode of the device and sets it to one. In this case, the AND 8 and 9 elements are preliminarily opened from the direct output of the trigger 2 for selecting the operating mode of the device. The inputs go to the inputs of the AND 6, 8 and 9 elements and the direct input of the AND 14 element. Depending on the position of the control the trigger 1, into which it is installed with a given probability P by the signals arriving at its inputs, the application enters either the first or the second service channel through the corresponding elements AND 6 and 8 and further through the elements OR 15 and 18, the elements AND 21 and 24 in the presence of unit potentials a straight triggers outputs 25 and 26 if both channels are available. In this case, elements 9 and 14 of the application do not pass through, since at their inverse inputs there are single potentials blocking these elements.

If one of the channels is busy, i.e. at the direct outputs of the flip-flops 25 or 26 there is a zero potential, then one of the corresponding elements AND 9 or 14 opening in this case allows the passage of the application to another free channel, and the absence of a single signal at the first inputs of the elements 21 and 21 or

24 prohibits the passage of applications into a busy channel.

In case both channels are busy, you get a rejection. The time of the end of the service quotation in the service channels is fixed by the transition of the corresponding triggers.

25 and 26 into one state by means of pulses arriving at their direct inputs from the outputs of the generator 5.

Consider the operation of the device in the second mode.

In order for the device to enter this mode, input 41 receives a signal at the input of trigger 2 and sets it to the zero state. In this case, unit 7 and elements 37, 38 and elements AND-NOT 16 and 17 are opened with a single potential from the inverse output of trigger 2. In this case, the applications pass through element 7 and 7, but elements 6 and 14 can also be opened, which also passes the applications. BUT

since the outputs of the elements And 6, 7 and 14 are combined in the first element OR, the multiplication of the requisitions in these elements after the combination in the element OR 15 is eliminated. Thus, the applications coming into the model, in the second mode, initially go to service only in trigger 25,

imitating the maintenance of the first phase.

Assume that during the next application, triggers 25 and 26 are in a single free

state, at the output of block 3 of distribution of service cycles, a single potential is formed, which corresponds to the operation of the device in the first phase of service, and three reverse

0, counters 19, 20, and 31 are in their initial zero state. The next application through the elements OR 15 and AND 21 enters the input of the trigger 25 and transfers it to the zero state corresponding to the maintenance of the application. In this case, elements 10-13 are locked and pulses from the generator 4 pulses do not pass through them. If the maintenance of this application

0 is completed before the end of the time interval of the first service phase, then at the moment when the service ends at the output of the pulse shaper 29 a short pulse is formed, which leads the reversible counter 31 to the first state and passed through the elements AND 38, OR 36, OR 18 and And 24, sets trigger 26 to the zero state. At the same time, through the AND 12 element, the summing input of the reversible counter 20 receives pulses from the generator 4. The AND element 12 is opened with single signals from block 3 and trigger 26. Thus, the counter 20 counts the required time interval that must be spent on servicing the application in the second the maintenance phase, while the model is transferred to the second maintenance cycle.

If, say, the service time of the application ends before the model enters the second service phase, then at the time of the end of the required service time under the action of the signal from block 5, the trigger 26 goes into one state, which will stop the flow of counting pulses through the And 12 element sum5

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Peaceful input of counter 20. With the onset of the second service phase, unit 3 forms a zero potential at its output, which, together with unit potentials, from the direct output of trigger 26 and the output of OR 23 opens an AND 13 element through which the subtracting input of counter 20 begins to flow counting pulses from generator 4. A reading is taken of the interval required for servicing the application, but already during the second service cycle, during which it was required to service this application. After reading the specified time interval, the counter 20 is zeroed out. As a result, the output potential of the elements OR 23 and 28 forms a zero potential, under the action of which the pulse shaper 30 forms a pulse of short duration which the counter 31 produces.

to zero state.

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If, say, the service time of the application ends after the model transitions into the second service phase, then at the moment the model enters the second service phase, element 12 is closed by the zero potential from unit 3. Thus, the time interval for which the will continue to simulate the service of the application in the second phase of the service after fixing the end of its service. The fixing of the end of service of this application occurs in trigger 26. When trigger 26 goes into one state, element 13 will open and the time interval for which it is required to continue to simulate the service in the second service cycle according to the algorithm described will be read.

If, during service, the next applications in the second phase of service will be received following the notes, served in the first phase and requiring the second phase of service, they will be received in a queue, i.e. transfer counter 31 to the following state. If trigger 26 is in a single free state when the service is not completed, the next application in the second service phase, i.e.

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at the output of the element OR 23 there will be a single potential, then none of the following wakes will go to the inverted input of the trigger 26, since the element 24 will be closed by a zero potential from the output of the AND-NOT element 17. This zero potential is generated by the single signals with inverse output of trigger 2 and from the output of the element OR 28. If there are applications in the queue waiting for the second phase of service, i.e. the state of the counter 31 will be greater than the first, then at the output of the element AND-HE 34 and the element OR 33 single potentials will be formed, which will open the element AND 35 (The element AND-HE 34 will form a zero potential at its output only in the first state of the counter 31) .

The transfer of one of these applications from the service queue to the second service phase will be as follows. At the time of termination of service of the next application in the second phase of service, pulse shaper 30 will generate a pulse of short duration, which, arriving at the subtracting input of counter 31, will reduce by one the state of this counter, and also pass through AND 35, 37, OR 36, OR 18 and AND 24 to the inverted input of the trigger 26 and transfer it to the zero state, which will record the receipt of this application for servicing the second phase. If counter 31 is in its limiting state, i.e. all the queue locations will be occupied and at the direct outputs of the counter 31 there will be single potentials arriving at the inputs of the AND-HE element 32, then the output of this element will generate a zero potential that will close the element 21 and thus prevent the passage of the next request. on the service of the first phase.

Consider the operation of the device when the service of the next application in the first phase of the service is completed before the end of the time interval of the first phase of the service. In this case, at the end of the time interval of the first phase of servicing, a zero potential from block 3 and a single potential from the inverse output of trigger 25 will open element 10, through which counting pulses from the generator 4 of pulses will be sent to summing input of reprr counter 13. Counter 13 will determine the time interval that will need to be spent on continuing the service of this application during the operation of the device in the first phase of the service. Termination of the definition of this time interval will come with the trigger 25 switching to a free single state, i.e. service time for applications. At the same time, the pulse shaping pulse generator 29 is not generated, since a single potential from the OR 22 element is present at the output of the OR element 27.

With the onset of the next time interval of the first service phase, element 11 will be opened with unit potentials from block 3, element 22 or from the direct output of trigger 25. Through this element 11 will begin to receive -countable pulses from generator 4 already at the subtracting input of counter 19, due to which will be the reading of the required time interval for the service of the application during the first cycle of the service. At the time of reading this time interval, the next applications will not pass for servicing, since element AND 10 will be closed with zero potential from the output of the AND-NOT element 16. This zero potential is formed under the influence of unit potentials entering the inputs of the AND-1 element from the inverse trigger output 2 and from the output of the element OR 22.

Upon completion of reading the required service time interval at the output of the elements OR 22 and 27

stray random service pulse generator, clock pulse generator, control trigger, mode selection trigger, first and second triggers, two pulse shapers, three reversing pulse counters, fourteen AND elements, six OR elements, two elements

NAND, the first inputs of the first, second, third, fourth, and fifth elements in AND are combined and are the information input of the device, the inputs of the control trigger are the 5 equalizing inputs of the device, and

The inputs of the mode selection trigger are the inputs for setting the device operation modes, the direct output of the first trigger is connected to the second input of the first AND element, the output of which is connected to the first input of the first OR element, the output of which is connected to the first input of the sixth AND element, the output of which is connected to zero

5 to the input of the first trigger, the direct output of which is connected to the second input of the sixth AND element and to the inverse input of the third AND element, the output of which is connected to the first input of the second OR element, the second input of which is connected to the output of the fifth AND element, and the output is connected to the first input of the seventh element And, the output of which is connected to the zero input

5 of the second trigger, the inverse output of which is connected to the first input of the eighth element And, the second input of which and the first input of the ninth element And connected to the output of the generator also

0 output pulses, the outputs of the eighth and ninth elements And are connected respectively to the summing and subtracting inputs of the first reversible pulse counter, the bit outputs

a zero potential is formed, after which 45 are connected respectively to

Claims (1)

As a result, the pulse shaper 29 will form a claim that requires servicing the second cycle, which will occur according to the indicated algorithm. At the same time, if there are free places in the queue for applications that are waiting for the second service cycle (counter 31 is not in the limit state), the device is ready to accept for service the first phase of the next applications. Invention Formula A device for simulating queuing systems containing 50 55 the inputs of the third element OR, the inverse output of the control trigger is connected to the second input of the fifth element AND, the third input of which and the third input of the third element AND are connected to the forward output of the mode selection trigger, the inverse output of which is connected to the first inputs of the tenth and eleventh elements AND and the second input of the second element AND, the output of which is connected to the second input of the first element OR, the third input of which is connected to the output of the even element AND, the inverse input which are connected respectively with the inputs of the third element OR, the inverse output of the control trigger is connected to the second input of the fifth element AND, the third input of which and the third input of the third element AND are connected to the forward output of the mode selection trigger, the inverse output of which is connected to the first inputs of the tenth and eleventh elements AND and the second input of the second element AND, the output of which is connected to the second input of the first element OR, the third input of which is connected to the output of the fourth element AND, the inverse input which is connected to the direct output of the second trigger and the second input of the seventh element And, the output of the twelfth element And is connected to the summing input of the second reversible pulse counter, the bit outputs of which are connected respectively to the inputs of the fourth element OR, the single inputs of the first and second trigger are connected respectively to the first and the second inputs of the random service pulse generator, the output of the first pulse generator is connected to the summing input of the third reversing pulse counter, The removable bit outputs of which are connected respectively to the inputs of the fifth OR element and the steps of the first NAND element, the output of the OR element 5 is connected to the first input of the thirteenth AND element, the second input of which is connected to the output of the second AND NAND element, and the third input of the thirteenth element I is connected to the output of the second pulse generator, the output of the thirteenth element I is connected to the second input of the tenth element I, characterized in that, in order to expand the functionality of the device by simulating an interrupt service in each of the phases of the two-phase service system, it additionally contains the third and fourth elements AND-NOT, the seventh and eighth elements OR, and the block for the distribution of the phases of service consisting of a series-connected pulse counter, a decoder, a dial floor and an OR element, and the output element The OR phase of the service phase distribution unit is connected to the third input of the eighth element AND, the second input of the ninth element AND, the first input of the fourteenth element AND, and the inverse input of the twelfth element AND devices And phase distribution count input pulse counter service block is connected to the output of the clock, the first entry mu twelfth AND gate and a second input of the fourteenth elements ten 15 20 25 thirty 35 40 45 50 And And, the output of which is connected to the subtractive input of the second reversible pulse counter, the inverse input of the mode selection trigger is connected to the first input of the third AND-NOT element and the first input of the fourth AND-NOT element, the output of which is connected to the third input of the seventh And element, and the third output element AND-NOT connected to the third input of the sixth element AND, the fourth input of which is connected to the output of the first element AND-NOT, the outputs of the fourth element OR are connected to the second input of the third AND-NC element, the third input of the fourteenth The AND element and the first input of the sixth OR element, whose output is connected to the input of the first pulse shaper, and the second input of the sixth OR element, is connected to the inverse output of the first trigger and the second input of the twelfth element AND, the output of the first trigger is connected to the fourth input of the fourteenth element AND, the output The third element OR is connected to the second input of the fourth element NAND, the third input of the ninth element AND and the first input of the seventh element OR, the second output of which is connected to the inverse output of the second t and the output of the seventh element OR is connected to the input of the second pulse driver, the output of which is connected to the subtractive input of the third reversible counter, the first direct discharge output of which is connected to the first input of the second element NAND, the remaining inputs of which are connected respectively to the inverse bit the outputs of the third reversible counter, starting with the second inverse discharge output, the direct output of the second trigger is connected to the fourth input of the ninth And element, and the output of the first driver is in connected with the second input of the eleventh element AND, the output of which and the output of the tenth element AND are connected respectively to the inputs of the eighth element OR, the output of which is connected to the third input of the second element OR. 39 1481790