Example Use Case: We have 100 users and they’ll be using data that can only be used once (meaning the application will not accept that data again, unless of course it is “reset” by the application team). We want that each “instance” of the seed data object inside the clip is assigned a unique value and that it changes from instance to instance. There can be other use cases where we just want this even though the data can be used several times.
This would be something similar to LoadRunner Select next row: Unique and Update value on: Each occurrence.
For setting this up, you’ll need to declare a property in a collection (page, transaction, page, etc.) that has the message where the value is used. Every seed data declaration is known in CloudTest as an “instance” of that object. You’ll need to create as many properties (instances) as new values from this property you want. These properties must be created in the collection that nests the message where you need the value. You can change the other settings depending on your needs, as for this example I’ve left the default values. Check “Save value for analytics” to see the values used after the composition is played with the widget “Property Value Composition Analysis”. You can change the other settings depending on your needs. The most important of these settings is the EOF Action. As for this example I’ve left the default values, but if you want to make sure the values are not reused and users ramp down when out of data, then select "Stop Track And Drain" so users don't reuse values already used. Check Setting Advanced Seed Data Options for more info on this. Group1 seed data property below (from the attached composition):
We'll use the most recommended set up for running a load test in CloudTest: Renew Parallel Repeats Enabled for the Track (Clip Repeats Disabled, image below).
Find attached a composition with this configuration (using Renew Parallel Repeats). Since it is set to renew parallel repeat, it will run infinitely, make sure to stop it after some iterations have completed to see the behavior. The composition is set to “Preview Mode”, meaning it will not be sending any traffic to the target but it will compute the seed data distribution. The attached composition has four properties declared in Group1, Transaction1 and Page3 and Page4 inside Transaction2.