There is another parameter we should consider here :
ShutdownTimeout
Number of seconds Caché should wait for shutdown to complete normally before timing out and forcing a shutdown. The default is 300 seconds (5 minutes). The range is 0 to a maximum of 231–1 seconds.
That means if there is a user process (or a background job !) that is not stopping immediately, Caché will by default wait 5 minutes before starting the system shutdown.
The time in 'WaitToKillServiceTimeout' shold be at least 'ShutdownTimeout', plus the max. time to really shut down Caché.
There is another parameter we should consider here :
ShutdownTimeout