Seed Data (from a flat file)

Seed data can be extracted from a URL file or resource and then accessed within the test.

Note: The values are not guaranteed to be used in order and contiguously. There can be gaps in the values selected from the given resource. Each Track gets a unique value.

How to

  1. Put a list of data values into a resource file.
    • To use this new feature, you need to put a flat file with a list of data (one item per line) in a location accessible to the CloudTest Maestro server as a URL.
    • This is not a CSV parser and only handles a single list—no arrays.
  2. Setup track properties
    • The Track Properties method works by assigning a single value from the file to a specific track. This is most useful for usernames. Each track (i.e. virtual user) will get its own username—and it is guaranteed that across the composition no other track gets that item from the file.
    • The track property needs to identify the file.


  3. Setup clip to use a track property
    • Instead of using clip properties to access the data, use track properties using this syntax in your clips: {%% prop : track : seedDataAccountName %%}


  4. Additional Considerations for data file creation and use in compositions
    • Always have a data file that is larger than the number of entries you will have. The amount of excess you need will depend on (1) the number of users/load generator and (2) the number of load generators.
    • When a composition is run, the data file is loaded onto the alpha load generator, cut into chunks, and distributed to all the servers. This is chunked evenly. Here’s how the math works:
      • The test is for 10,000 users and will run with 500 users/load generator. This means 20 load generators are required (10,000/500).
      • The data file has 11,000 entries in it. This means each of the 20 load generators will get 550 entries from the file (11,000/20).
      • You want to make sure the number of entries in the file (in this case, 550) exceeds the number of users/load generator (in this case, 500). If not, you need more entries in the seed file.