Processes Step by Step

Experimentation

The Model Trace

   
 

We will take a short look at the trace file now, because this file will let you gain a good insight of the model's behaviour. It shows how the processes in our model interact and how they become activated by the DESMO-J scheduler.

The trace file starts with messages showing that recording the trace and debug output is started. Then the two van carriers start their life cycle by inserting themselves into the idle VC queue and then passivating, since there are no trucks waiting yet. After this, it's the turn for the truck generator (named TruckArrival) to activate the first truck. This truck requests the service of Van Carrier#1 (the first in line inside the idleVCQueue) and then passivates itself (remember that trucks are modelled as passive customers whereas the van carriers are the active servers during their joint activity of loading a container). Van Carrier#1 regains control, removes Truck#1 from the queue and then holds for the period of simulation time it takes to service the truck. 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 7.3875.

In the meantime, the third truck arrives at the terminal (at 1.0507) and the service of the first truck is finished (at 3.1711) which results in Van Carrier#1 moving on to load the newly arrived Truck#3 and Truck#1 terminating (leaving the system). 

 
ProcessesExampleExperiment - Trace




 
time
event
entity
action(s)


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


    Debug switched on


    activates 'Van Carrier#1' now


    activates 'Van Carrier#2' now


   Van Carrier#1inserts itself into 'idle VC Queue'


    passivates


   Van Carrier#2inserts itself into 'idle VC Queue'


    passivates


   TruckArrival#1activates 'Truck#1' after 'TruckArrival#1'


   Truck#1TruckQueuelength: 1


    removes Van Carrier#1 from 'idle VC Queue'


    activates 'Van Carrier#1' after 'Truck#1'


    passivates


   Van Carrier#1removes Truck#1 from 'Truck Queue'


    holds for 3.1666 until 3.1666


 0.9500 TruckArrival#1activates 'Truck#2' after 'TruckArrival#1'


   Truck#2TruckQueuelength: 1


    removes Van Carrier#2 from 'idle VC Queue'


    activates 'Van Carrier#2' after 'Truck#2'


    passivates


   Van Carrier#2removes Truck#2 from 'Truck Queue'


    holds for 6.4166 until 7.3666


 1.0333 TruckArrival#1activates 'Truck#3' after 'TruckArrival#1'


   Truck#3TruckQueuelength: 1


    passivates


 3.1666 Van Carrier#1activates 'Truck#1' now


    removes Truck#3 from 'Truck Queue'


    holds for 5.3333 until 8.5000


   Truck#1Truck was serviced and leaves system.


    Truck#1 terminates

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. 

 


 13.5666 Van Carrier#2activates 'Truck#4' now


    removes Truck#7 from 'Truck Queue'


    holds for 6.2666 until 19.8333


   Truck#4Truck was serviced and leaves system.


    Truck#4 terminates


 13.7166 TruckArrival#1activates 'Truck#8' after 'TruckArrival#1'


   Truck#8TruckQueuelength: 1


    passivates


 15.6166 TruckArrival#1activates 'Truck#9' after 'TruckArrival#1'


   Truck#9TruckQueuelength: 2


    passivates


 15.8666 TruckArrival#1activates 'Truck#10' after 'TruckArrival#1'


   Truck#10TruckQueuelength: 3


    passivates


 17.0666 Van Carrier#1activates 'Truck#6' now


    removes Truck#8 from 'Truck Queue'


    holds for 4.6333 until 21.7000


   Truck#6Truck was serviced and leaves system.


    Truck#6 terminates


 19.7333 TruckArrival#1activates 'Truck#11' after 'TruckArrival#1'


   Truck#11TruckQueuelength: 3


    passivates


 19.8333 Van Carrier#2activates 'Truck#7' now


    removes Truck#9 from 'Truck Queue'


    holds for 4.5500 until 24.3833


   Truck#7Truck was serviced and leaves system.


    Truck#7 terminates


 20.1000 TruckArrival#1activates 'Truck#12' after 'TruckArrival#1'


   Truck#12TruckQueuelength: 3


    passivates


 20.6500 TruckArrival#1activates 'Truck#13' after 'TruckArrival#1'


   Truck#13TruckQueuelength: 4


    passivates


 21.7000 Van Carrier#1activates 'Truck#8' now


    removes Truck#10 from 'Truck Queue'


    holds for 4.4666 until 26.1666


   Truck#8Truck was serviced and leaves system.


    Truck#8 terminates


 21.8000 TruckArrival#1activates 'Truck#14' after 'TruckArrival#1'


   Truck#14TruckQueuelength: 4


    passivates


 22.6333 TruckArrival#1activates 'Truck#15' after 'TruckArrival#1'


   Truck#15TruckQueuelength: 5


    passivates


 24.3833 Van Carrier#2activates 'Truck#9' now


    removes Truck#11 from 'Truck Queue'


    holds for 3.3333 until 27.7166


   Truck#9Truck was serviced and leaves system.


    Truck#9 terminates


 26.1666 Van Carrier#1activates 'Truck#10' now


    removes Truck#12 from 'Truck Queue'


    holds for 5.3500 until 31.5166


   Truck#10Truck was serviced and leaves system.


    Truck#10 terminates


 27.6666 TruckArrival#1activates 'Truck#16' after 'TruckArrival#1'


   Truck#16TruckQueuelength: 4


    passivates


 27.7166 Van Carrier#2activates 'Truck#11' now


    removes Truck#13 from 'Truck Queue'


    holds for 4.6666 until 32.3833


   Truck#11Truck was serviced and leaves system.


    Truck#11 terminates


 31.5166 Van Carrier#1activates 'Truck#12' now


    removes Truck#14 from 'Truck Queue'


    holds for 6.4333 until 37.9500


   TruckArrival#1activates 'Truck#17' after 'TruckArrival#1'


   Truck#17TruckQueuelength: 3


    passivates


   Truck#12Truck was serviced and leaves system.


    Truck#12 terminates


 32.2833 TruckArrival#1activates 'Truck#18' after 'TruckArrival#1'


   Truck#18TruckQueuelength: 4


    passivates


 32.3833 Van Carrier#2activates 'Truck#13' now


    removes Truck#15 from 'Truck Queue'


    holds for 3.0000 until 35.3833


   Truck#13Truck was serviced and leaves system.


    Truck#13 terminates


 35.2666 TruckArrival#1activates 'Truck#19' after 'TruckArrival#1'


   Truck#19TruckQueuelength: 4


    passivates


 35.3833 Van Carrier#2activates 'Truck#15' now


    removes Truck#16 from 'Truck Queue'


    holds for 6.4166 until 41.8000


   Truck#15Truck was serviced and leaves system.


    Truck#15 terminates


 37.9500 Van Carrier#1activates 'Truck#14' now


    removes Truck#17 from 'Truck Queue'


    holds for 6.9000 until 44.8500


   Truck#14Truck was serviced and leaves system.


    Truck#14 terminates


 41.8000 Van Carrier#2activates 'Truck#16' now


    removes Truck#18 from 'Truck Queue'


    holds for 6.0666 until 47.8666


   Truck#16Truck was serviced and leaves system.


    Truck#16 terminates


 44.8500 Van Carrier#1activates 'Truck#17' now


    removes Truck#19 from 'Truck Queue'


    holds for 6.6833 until 51.5333


   Truck#17Truck was serviced and leaves system.


    Truck#17 terminates


 46.7000 TruckArrival#1activates 'Truck#20' after 'TruckArrival#1'


   Truck#20TruckQueuelength: 1


    passivates



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