SCF Reference Manual for the Kernel Subsystem

• If you create a process that stops or abends frequently, and you specify a high AUTORESTART
value, system performance is negatively affected. To reduce the impact on system performance,
you can use the “ALTER Command (Sensitive Command)” (page 85) to give the process a
lower AUTORESTART value.
Table 5 lists the reasons a generic process can be stopped and, for each reason, whether the
persistence count is decremented.
Table 5 Effect of Stopping on the Persistence of a Generic Process
Persistence Count IsReasons a Generic Process Is Stopped
Not decrementedIt was never started (the start mode is MANUAL or DISABLED).
Not decrementedIt was started, but its processor was down at the time.
Not decrementedIt was started, but its processor went down later.
DecrementedIt was stopped outside SCF (for example, by a TACL STOP command).
Reset to 0It was stopped inside SCF by an ABORT command.
DecrementedIt abended.
0Its persistence count was decremented to 0.
• The ABORT command effectively sets the persistence count to zero. A processor reload does
not restart an aborted process. To restart a generic process in the STOPPED object state,
ABORTED substate, you must either issue an SCF START command or load the system. See
“Restarting an Aborted Generic Process” (page 48).
• The START command sets or resets the persistence count to its configured value.
• The SCF INFO command displays the configured (not the current) persistence count.
System Load Considerations
The effect on a generic process of a system load (and initial reload of the processor in which the
generic process is configured) depends on the configured start mode. Any process with a start
mode other than MANUAL or DISABLED is started when its processor comes up, regardless of its
configured or current persistence count. After the system load finishes, the persistence count is reset
to its configured value.
Table 6 lists these system load consideration.
Table 6 System Load Considerations for Persistence
SituationConsideration
Has any valueGeneric process object state prior to system load…If…
Is KERNEL, SYSTEM, or APPLICATIONStart mode…and if…
Is reset to its configured valuePersistence count…Then…
Restarts the generic process regardless of configured
persistence count. ($ZPM might restart the generic
$ZPM…and…
process in the backup processor, if that processor
comes up before the primary processor.)
46 Configuring and Managing Generic Processes