The data in this table is generated from login and logoff events from the clients. This data goes into the Evt_AeX_Client_LogOn table. Then, on a nightly basis, the NS.Machine Usage Generation scheduled task runs. This task runs the sp_GenerateMachineUsageData stored procedure which populates the data in the Inv_AeX_AC_Machine_Usage table.
The Machine Usage table contains specific time data for each user that was logged into a machine and the rank of each user based upon who was logged on longest.
Columns in the AeX_AC_Machine_Usage
Month User Domain Hours logged in Rank
April ADMINISTRATOR <domain> 96.566666666666706 1
Primary User data comes specifically from the AeXUserMonitorlog.xml file on a client which the Altiris Agent uses to populate the AC_Primary_User dataclass.
It specifies only the primary user and domain for a particular month for each computer.
Columns in the AeX_AC_Primary_User
Month User Domain Server Generated
December Administrator <Domain> NULL
So in summary, Primary User data is generated by the Altiris Agent during basic inventory based upon data in the AeXUserMonitorLog.xml file.
Machine Usage data is then generated nightly based upon logon/logoff events located in the the Evt_AeX_Client_LogOn table.