if the command "GO BRMS" is executed first time a day, it takes 1 to 3 minutes for execution (disply BRMS main menu).
Afterwards respond time is "normal", within seconds.
If repeated later again (after 1h or more) it takes again minutes.
This situation is not Job-depending and not a configuration mistake.
May be, the bad performance is caused by "first loading BRMS objects in main storage" (explanation from IBM Support), but i need a practical solution to speed up first, initial BRMS commands.