Operation Mode Switches

Use

When operation modes are switched, the R/3 System work processes are redistributed automatically without stopping and restarting the instances.

Only the work process types are changed. For example, a work process used as a dialog process can be switched for use as a background process.

The new process type is not activated until the process is free. This means that a process may not be switched immediately. Instead, a process is set to be switched when next possible. For example, if all background processes to be switched to dialog processes still have jobs, the processes are switched one by one when the jobs are completed.

Processing is not interrupted. Normal system operation continues uninterrupted during the operation mode switch.

Operation mode switches are recorded in the system log. The old process type and the new process type are recorded for each work process that is switched.

Additional Information on Operation Mode Switches

System Startup

When a server is started, it first runs without an operation mode. The number of work processes and their distribution is defined in the instance profile used to start the server.

The status of the operation mode is checked at regular time intervals and the operation mode defined as active in the timetable is activated automatically. If there is no operation mode for the current time in the timetable, an operation mode is not activated.

Initial Operation Mode Switch

The first time an application server is switched to an operation mode, this is done by the ABAP program SAPMSSY6 . This program runs cyclically, collects the alert values, performs profile checks and creates DUMMY operation modes. The profile parameter rdisp/autoabaptime controls what intervals the program runs at. The default cycle is 300 seconds.

SAPMSSY6 only switches operation modes if the application server is not running in an operation mode. Normally, the system is switched within 5 minutes of system startup to the operation mode defined in the timetable.

SAPMSSY6 does not perform a continuous switch. This means that a manual operation mode switch will not be switched back after 5 minutes.

Timed Operation Mode Switch

The exact times for operation mode switches are defined in the timetable.

A timed operation mode switch is started by the job scheduler ( SAPMSSY2 ). The operation mode switch can therefore only be performed automatically if at least one job scheduler is running in the R/3 System. This means that at least one background work process and parameter rdisp/btctime > 0 must be available.

The switch is always done for all servers defined in the operation mode.

If more than one job scheduler is running, only one job scheduler can activate an operation mode switch.