Hello Phillip,
You can refer to the below KBA for User Session Scenarios while a user logs into BusinessObjects:
1862925 - Session handling and tuning
For the connection from a Report to the its database you need to check the setting done on the respective report server's properties.
So if you are refreshing a Crystal Report, you should check the Maximum concurrent jobs setting on the Crystal Reports 2011/2013/2016 Processing Server.
Regards,
Vaidehi