Parameter Simulation dialog box

This dialog box allows you to view a simulation of the behavior of a file parameter.

To access
Design > Parameters > Parameter List.
Select a parameter and click Simulate Parameter
Important information
  • This feature is only relevant for file type parameters.

  • Not all types of Parameter Substitution can be simulated. If you select Select next row: Same line as... or Update value on: Each occurrence, then the Parameter Simulation dialog box will not open.

  • VuGen can simulate up to 256 iterations and 256 Vusers.

  • Maximum parameter value length: 100 characters.
  • Run Indefinitely is compliant with the Real-life schedule in the Scheduler of the Controller.

  • If you select Select next row: Unique in the Parameter List dialog, then each Vuser is assigned a unique range of rows from which the Simulator will substitute values (for that Vuser).

    Note: If you have more than one unique parameter, you need to verify that each parameter has defined values for all Vusers.

  • With this setting, the default selection in the Allocate Vuser values in the Controller section is Automatically allocate block size. When you run the simulation, the range allocation takes place in accordance with your Scenario run mode selection.
    If you change the default selection to Allocate x values for each Vuser, then the Vusers are allocated the amount of values you specify, ignoring your Scenario run mode selection.

User interface elements are described below:

UI Element
The number of Vusers to run in the simulation.
Scenario run mode
  • Run until completion. Enter the number of iteration to run or select Take number of iteration from Runtime Settings.

  • Run indefinitely. Simulates the run indefinitely option in the controller. VuGen only actually simulates the number of iterations you specify.

Runs the parameter simulation. The values of each parameter substitution are displayed.


In the following examples, the settings in the Parameter List dialog box are:

  • Values for the new parameter. Value1 to Value7

  • Select next row. Unique

  • When out of rows. Continue with last value

  • Allocate Vuser values in the Controller. Automatically allocate block size

Scenario run mode: Run until completion

Three Vusers, Scenario run mode to Run until completion, and selected three iterations:

Run Mode

When the scenario run mode is set to Run until completion, the number of rows that each Vuser receives is the same as the number of iterations. The range allocation stops when there are no longer enough rows in the table.

As the simulation is run, the first Vuser takes the first three values (because this was the number of iterations). The second Vuser takes the next three values. The third Vuser takes the remaining value in the first iteration. For the remaining iterations, since the When out of values option in the Parameter List dialog box was set to Continue with last value, the third Vuser continues with the same value.

A fourth Vuser would have failed.

Scenario run mode: Run indefinitely

In the following example, the user has selected 3 Vusers and set the Scenario run mode to Run indefinitely and selected to show 3 iterations.

When the Scenario run mode is set to Run indefinitely, the allocated range for each Vuser is calculated by dividing the number of cells in the .dat file by the number of Vusers. In this scenario, that is 7/3 = 2 (The simulator takes the closest smaller integer.).

As the simulation is run, the first Vuser takes Value1 and Value2. The second Vuser takes Value3 and Value4 and the third Vuser takes Value5 and Value6. Since there are were only 3 Vusers, Value7 was not distributed.

Note: If you hold the mouse over the cells in the first column of the table, a tool tip appears with information about which values were assigned to that Vuser.

If you hold the mouse over cells which were not assigned values, a tool tip appears with the reason no values were assigned.

A tool tip does not appear if a proper value was assigned.

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