Events Step by Step

Experimentation

The Model Trace

   
 

We will take a short look into the trace file now, because this file will let you gain a good insight of the model's behaviour. It shows how the entities in our model interact and how the events are scheduled.

The trace file starts with messages showing that recording the trace and debug output is started. Then the external truck generator event schedules the arrival of the first truck (TruckArrivalEvent#1) and reschedules itself for simulation time 0.9500 when the next truck is due to enter the system. During the first truck arrival event Truck#1 inserts itself into the queue of waiting trucks. It then proceeds to remove the first idle van carrier (VanCarrier#1) from its queue. Finally, a new service end event is scheduled for simulation time 3.1666. The next thing happening in our model is the arrival of another truck at simulation time 0.9500. This truck is serviced by the second van carrier until simulation time 7.3666.

In the meantime, the third truck arrives at the terminal (at 1.0333) and the service of the first truck is finished (at 3.1666) which results in Truck#1 leaving the system and VanCarrier#1 moving on to load the newly arrived Truck#3. 

EventExampleExperiment - Trace




time
event
entity
action(s)


 0.0000--------Trace switched on


    Debug switched on


    schedules 'TruckGenerator#1' at 0.0000.


  TruckGenerator#1 schedules 'TruckArrivalEvent#1' of 'Truck#1' at 0.0000.


    schedules 'TruckGenerator#1' at 0.9500.


  TruckArrivalEvent#1Truck#1inserts itself into 'Truck Queue'


    TruckQueueLength: 1


    removes VanCarrier#1 from 'idle VC Queue'


    removes itself from 'Truck Queue'


    schedules 'ServiceEndEvent#1' of 'VanCarrier#1' and 'Truck#1' at 3.1666.


 0.9500TruckGenerator#1----schedules 'TruckArrivalEvent#2' of 'Truck#2' at 0.9500.


    schedules 'TruckGenerator#1' at 1.0333.


  TruckArrivalEvent#2Truck#2inserts itself into 'Truck Queue'


    TruckQueueLength: 1


    removes VanCarrier#2 from 'idle VC Queue'


    removes itself from 'Truck Queue'


    schedules 'ServiceEndEvent#2' of 'VanCarrier#2' and 'Truck#2' at 7.3666.


 1.0333TruckGenerator#1----schedules 'TruckArrivalEvent#3' of 'Truck#3' at 1.0333.


    schedules 'TruckGenerator#1' at 5.6500.


  TruckArrivalEvent#3Truck#3inserts itself into 'Truck Queue'


    TruckQueueLength: 1


 3.1666ServiceEndEvent#1VanCarrier#1 and Truck#1Truck#1 leaves the terminal


    removes Truck#3 from 'Truck Queue'


    schedules 'ServiceEndEvent#3' of 'VanCarrier#1' and 'Truck#3' at 8.5000.

Later on, a number of trucks arrive in short succession while both van carriers are busy, resulting in the queue of waiting trucks starting to build up. But as the report has already proven, they are able to decrease the queue again. 

 


 13.5666ServiceEndEvent#4VanCarrier#2 and Truck#4Truck#4 leaves the terminal


    removes Truck#7 from 'Truck Queue'


    schedules 'ServiceEndEvent#7' of 'VanCarrier#2' and 'Truck#7' at 19.8333.


 13.7166TruckGenerator#1----schedules 'TruckArrivalEvent#8' of 'Truck#8' at 13.7166.


    schedules 'TruckGenerator#1' at 15.6166.


  TruckArrivalEvent#8Truck#8inserts itself into 'Truck Queue'


    TruckQueueLength: 1


 15.6166TruckGenerator#1----schedules 'TruckArrivalEvent#9' of 'Truck#9' at 15.6166.


    schedules 'TruckGenerator#1' at 15.8666.


  TruckArrivalEvent#9Truck#9inserts itself into 'Truck Queue'


    TruckQueueLength: 2


 15.8666TruckGenerator#1----schedules 'TruckArrivalEvent#10' of 'Truck#10' at 15.8666.


    schedules 'TruckGenerator#1' at 19.7333.


  TruckArrivalEvent#10Truck#10inserts itself into 'Truck Queue'


    TruckQueueLength: 3


 17.0666ServiceEndEvent#6VanCarrier#1 and Truck#6Truck#6 leaves the terminal


    removes Truck#8 from 'Truck Queue'


    schedules 'ServiceEndEvent#8' of 'VanCarrier#1' and 'Truck#8' at 21.7000.


 19.7333TruckGenerator#1----schedules 'TruckArrivalEvent#11' of 'Truck#11' at 19.7333.


    schedules 'TruckGenerator#1' at 20.1000.


  TruckArrivalEvent#11Truck#11inserts itself into 'Truck Queue'


    TruckQueueLength: 3


 19.8333ServiceEndEvent#7VanCarrier#2 and Truck#7Truck#7 leaves the terminal


    removes Truck#9 from 'Truck Queue'


    schedules 'ServiceEndEvent#9' of 'VanCarrier#2' and 'Truck#9' at 24.3833.


 20.1000TruckGenerator#1----schedules 'TruckArrivalEvent#12' of 'Truck#12' at 20.1000.


    schedules 'TruckGenerator#1' at 20.6500.


  TruckArrivalEvent#12Truck#12inserts itself into 'Truck Queue'


    TruckQueueLength: 3


 20.6500TruckGenerator#1----schedules 'TruckArrivalEvent#13' of 'Truck#13' at 20.6500.


    schedules 'TruckGenerator#1' at 21.8000.


  TruckArrivalEvent#13Truck#13inserts itself into 'Truck Queue'


    TruckQueueLength: 4


 21.7000ServiceEndEvent#8VanCarrier#1 and Truck#8Truck#8 leaves the terminal


    removes Truck#10 from 'Truck Queue'


    schedules 'ServiceEndEvent#10' of 'VanCarrier#1' and 'Truck#10' at 26.1666.


 21.8000TruckGenerator#1----schedules 'TruckArrivalEvent#14' of 'Truck#14' at 21.8000.


    schedules 'TruckGenerator#1' at 22.6333.


  TruckArrivalEvent#14Truck#14inserts itself into 'Truck Queue'


    TruckQueueLength: 4


 22.6333TruckGenerator#1----schedules 'TruckArrivalEvent#15' of 'Truck#15' at 22.6333.


    schedules 'TruckGenerator#1' at 27.6666.


  TruckArrivalEvent#15Truck#15inserts itself into 'Truck Queue'


    TruckQueueLength: 5


 24.3833ServiceEndEvent#9VanCarrier#2 and Truck#9Truck#9 leaves the terminal


    removes Truck#11 from 'Truck Queue'


    schedules 'ServiceEndEvent#11' of 'VanCarrier#2' and 'Truck#11' at 27.7166.


 26.1666ServiceEndEvent#10VanCarrier#1 and Truck#10Truck#10 leaves the terminal


    removes Truck#12 from 'Truck Queue'


    schedules 'ServiceEndEvent#12' of 'VanCarrier#1' and 'Truck#12' at 31.5166.


 27.6666TruckGenerator#1----schedules 'TruckArrivalEvent#16' of 'Truck#16' at 27.6666.


    schedules 'TruckGenerator#1' at 31.5166.


  TruckArrivalEvent#16Truck#16inserts itself into 'Truck Queue'


    TruckQueueLength: 4


 27.7166ServiceEndEvent#11VanCarrier#2 and Truck#11Truck#11 leaves the terminal


    removes Truck#13 from 'Truck Queue'


    schedules 'ServiceEndEvent#13' of 'VanCarrier#2' and 'Truck#13' at 32.3833.


 31.5166ServiceEndEvent#12VanCarrier#1 and Truck#12Truck#12 leaves the terminal


    removes Truck#14 from 'Truck Queue'


    schedules 'ServiceEndEvent#14' of 'VanCarrier#1' and 'Truck#14' at 37.9500.


  TruckGenerator#1----schedules 'TruckArrivalEvent#17' of 'Truck#17' at 31.5166.


    schedules 'TruckGenerator#1' at 32.2833.


  TruckArrivalEvent#17Truck#17inserts itself into 'Truck Queue'


    TruckQueueLength: 3


 32.2833TruckGenerator#1----schedules 'TruckArrivalEvent#18' of 'Truck#18' at 32.2833.


    schedules 'TruckGenerator#1' at 35.2666.


  TruckArrivalEvent#18Truck#18inserts itself into 'Truck Queue'


    TruckQueueLength: 4


 32.3833ServiceEndEvent#13VanCarrier#2 and Truck#13Truck#13 leaves the terminal


    removes Truck#15 from 'Truck Queue'


    schedules 'ServiceEndEvent#15' of 'VanCarrier#2' and 'Truck#15' at 35.3833.


 35.2666TruckGenerator#1----schedules 'TruckArrivalEvent#19' of 'Truck#19' at 35.2666.


    schedules 'TruckGenerator#1' at 46.7000.


  TruckArrivalEvent#19Truck#19inserts itself into 'Truck Queue'


    TruckQueueLength: 4


 35.3833ServiceEndEvent#15VanCarrier#2 and Truck#15Truck#15 leaves the terminal


    removes Truck#16 from 'Truck Queue'


    schedules 'ServiceEndEvent#16' of 'VanCarrier#2' and 'Truck#16' at 41.8000.


 37.9500ServiceEndEvent#14VanCarrier#1 and Truck#14Truck#14 leaves the terminal


    removes Truck#17 from 'Truck Queue'


    schedules 'ServiceEndEvent#17' of 'VanCarrier#1' and 'Truck#17' at 44.8500.


 41.8000ServiceEndEvent#16VanCarrier#2 and Truck#16Truck#16 leaves the terminal


    removes Truck#18 from 'Truck Queue'


    schedules 'ServiceEndEvent#18' of 'VanCarrier#2' and 'Truck#18' at 47.8666.


 44.8500ServiceEndEvent#17VanCarrier#1 and Truck#17Truck#17 leaves the terminal


    removes Truck#19 from 'Truck Queue'


    schedules 'ServiceEndEvent#19' of 'VanCarrier#1' and 'Truck#19' at 51.5333.


 46.7000TruckGenerator#1----schedules 'TruckArrivalEvent#20' of 'Truck#20' at 46.7000.


    schedules 'TruckGenerator#1' at 50.7500.


  TruckArrivalEvent#20Truck#20inserts itself into 'Truck Queue'


    TruckQueueLength: 1



   
  http://desmoj.sourceforge.net/tutorial/events/exp3.html