Idle time is the number of seconds that a connection remains inactive, waiting for user input. An inactive connection continues to use server resources, and may also hold resources (for example, locks) that can block other active processes running on the same server.
idle_time allows you to set time limits for idle connections. If a connection is idle beyond the limit set, SAP ASE stops the process running the connection or issues a warning.
sp_add_resource_limit user, application, time_range, idle_time , kill_time, enforcement_time, action, scope
sp_add_resource_limit sa, isql, 'at all times', idle_time, 10,2,4,8
See the Reference Manual: Procedures.