What exactly "Clean User Session" job does and what data it cleans and where. Is there any default Inactivity period for inactive sessions
Release : All
The purpose of the Clean User Sessions Job is to perform maintenance/purge data as the Clean User Sessions Job will remove user session records. It executes the following stored procedure called CMN_SESSION_CLEANUP_SP, which has some delete statements against the sessions table like CMN_SESSIONS table.
This table only contains user info while this user is logged in, once the user logs out, the row is removed from the table. If the user doesn't use the Logout link, the session may be still kept. For example, if a user closes the browser window without logging out, Clarity will leave the session active forever (something that won't be cleaned by the Clean User Session job)
When running the job the logged in users are not kicked off their session. While running the Clean job users that are logged in will not be impacted at all.