As an administrator, you can see if there are executing jobs, but you can't see if people are doing other activities to know if you can restart the service without interfering with their work. There is no way to necessary send out a message to all current users to close their session. Just having a list of names and perhaps current panel and time of login. When they get the security cookie you can update a monitoring table for session starting etc.
Environment
Release : All Supported Releases
Component : CA Test Data Manager
Cause
N/A
Resolution
TDM Portal is based on REST API calls.
REST API calls are stateless by nature, meaning no session remains active.
With no sessions active we cannot provide this feature request.