Setting the access mode of a datapool in Rational Performance Tester

Answer

In Rational Performance Tester there are 3 access modes to choose from when using datapools:

Shared (per machine) (This is the default mode)

Virtual users on each computer draw from a shared view of the datapool, with datapool rows apportioned to them collectively in sequential order, on a first-come-first-served basis.

This option makes it likely that the virtual users or loop iterations will use data from different rows and that the server will see variable data. The exact row access order among all virtual users or iterations cannot be predicted, because this order depends on the test execution order and the duration of the test on each computer.

Private

Each virtual user draws from a private view of the datapool, with datapool rows apportioned to each user in sequential order.

This option offers the fastest test execution and ensures that each virtual user gets the same data from the datapool in the same order. However, this option most likely results in different virtual users using the same row. The next row of the datapool is used only if you add the test that is using the datapool to a schedule loop with more than one iteration.

Segmented (per machine)

Virtual users on each computer draw from a segmented view of the datapool, with data apportioned to them collectively from their segment in sequential order, on a first-come-first-served basis. The segments are computed based on how a schedule apportions virtual users among computers. For example, if a schedule assigns 25% of users to group 1 and 75% to group 2, and assigns these groups to computer 1 and computer 2, the computer 1 view will consist of the first 25% of datapool rows and the computer 2 view will consist of the remaining 75% of rows.

This option prevents virtual users from selecting duplicate values (for example, account IDs). If you disable wrapping, no row can be used more than once.

Note: This option requires the datapool to contain only one equivalence class. With the other options, equivalence classes are ignored.