Imagine a test with multiple test cases that will run over multiple load generators. This article will go over how to count how many Virtual Users (VUs) will execute each test case in a DMTC.

Rule of thumb

Before a test starts, StresStimulus allocates VUs between load generators and test cases in the following order:

1. Allocate VUs between load generators according to each generator's mix weight.
2. Within each load generator, allocate VUs between each test case according to each test case's mix weight. The test case mix weight on the load generator is called Gen Mix Weight.

Determining mix weights

Let's take a test that will have a maximum load of 1000 VUs between 4 test cases running across 3 load generators (named East, West, Local). Below is an example of desired VU distributions between the test cases.

Click the Configure VU distribution > By Load Agent - TC... button to bring up the VU configuration dialog

Distribute VUs between load agents

According to the rule of thumb, first, the 1000 VUs are distributed between load agents. In the dialog, select the All Load Agents node and modify the Mix Weight column on the left. The VU Distribution column shows the actual number of VUs that will be executed on the agent. 

Load Agent  Mix Weight Percent Number of VUs East 500 50 500 West 300 30 300 Local 200 20 200 When the sum of the mix weights equal sum of VUs to distribute, then the individual mix weights equal the individual VU distribution.

Distribute VUs between test cases

Now that the VUs have been distributed between the load agents, the test case distribution can be configured on each agent individually.

Select an agent node to modify the test case mix weights