This MaxRunnersPerQueue option defines the maximum
number of queue processors that can run in parallel in any given
queue group. Note that this differs from the
MaxQueueChildren option (MaxQueueChildren), which sets the total limit for all queue
The MaxRunnersPerQueue option is declared like
O MaxRunnersPerQueue=num configuration file (V8.12 and later)
-OMaxRunnersPerQueue=num command line (V8.12 and later)
define(`confMAX_RUNNERS_PER_QUEUE', `num') mc configuration (V8.12 and later)
Here, num is of type
numeric. If num is
negative, nonnumeric, or zero, no limit is set. If
num is positive (the default is 1), that
limit is applied to each queue group.
Note that this limit is overridden by the Runners=
equate, of the Q configuration file lines (Section 11.4.2), and that a Runners=0
disables all queue processing for a queue group. If a
Runners= is not specified for a queue group, this
MaxRunnersPerQueue option sets the default. Also
note that this MaxRunnersPerQueue option is
effective only if the MaxQueueChildren option is
also given a positive value.
The MaxRunnersPerQueue option is not safe. If
specified from the command line, it can cause
sendmail to relinquish its special privileges.