rdisp/gui_auto_logout is a SAP Parameter attribute which is used to control Maximum idle time for SAP GUI connections information. This is available within R/3 SAP systems depending on the version and release level.
Below is the standard documentation available and a few details of the attributes values .
You can define that inactive SAP GUI users are automatically logged off
of an SAP system after a predefined period of time. The parameter
configures this time period.
Automatic logoff in the SAP system is deactivated by default (value 0),
that is, the users are not logged off even if they do not execute any
actions for a longer period of time.
See SAP Parameter Documentation for full SAP documentation for this profile parameter.