Collective elements apply to all users in a scenario, and they require the Scenarios module to generate line-by-line queries of the dps_user and dps_user_scenario tables. These queries can run slowly if the number of profiles is high.

Consider the following example:

This scenario generates a query similar to the following:

FROM dps_user t1
WHERE ((t1.login IS NOT NULL)
AND NOT EXISTS (SELECT * FROM dps_user_scenario
WHERE id = AND ind_scenario_id IN
( SELECT FROM dss_ind_scenario tt1
WHERE (tt1.creator_id = '4000001'))))

The query searches the dps_user table for profiles that have a defined login name, and it also searches the dps_user_scenario table to make sure none of those profiles already has a scenario instance created for this scenario. As more profiles are found that match the query, more scenario instances are created, which in turn adds more lines to the dps_user_scenario table. For sites with an unusually large number of profiles, this process can eventually become very slow.

You can improve performance by checking that the maxBatchSize setting in the Scenario Manager component is set to at least the default value, 1000, and adjusting it if necessary A higher setting enables the Scenarios module to process more profiles with each iteration of the query.

To examine the profile queries that your scenarios generate, turn on the loggingDebug property for the /atg/userprofiling/ProfileAdapterRepository component. The queries appear in the <ATG10dir>\home\logs\debug.log file.