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SCHED_4BSD(4)		    Kernel Interfaces Manual		 SCHED_4BSD(4)

NAME
       sched_4bsd -- 4.4BSD scheduler

SYNOPSIS
       options SCHED_4BSD

DESCRIPTION
       The sched_4bsd scheduler	is the traditional system scheduler, providing
       both  high throughput and solid interactive response in the presence of
       load.

       The following sysctls are relevant to the operation of sched_4bsd:

       kern.sched.name
	       This read-only sysctl reports the name of the active scheduler.

       kern.sched.quantum
	       This read-write sysctl reports or sets the length of the	 quan-
	       tum (in micro-seconds) granted to a thread.

       kern.sched.ipiwakeup.enabled
	       This  read-write	 sysctl	sets whether or	not the	scheduler will
	       generate	an inter-processor interrupt (IPI) to an idle CPU when
	       a thread	is woken up.  Otherwise, idle CPUs will	wait until the
	       next clock tick before looking for new work.

       kern.sched.preemption
	       This read-only sysctl reports whether or	not the	kernel is con-
	       figured to support preemption, which reduces the	latency	to run
	       lower priority threads on wakeup.

       Some sysctls will be available only on systems supporting SMP.

SEE ALSO
       sched_ule(4), sysctl(8)

HISTORY
       The sched_4bsd scheduler	has been present, in various forms, since  the
       inception of BSD.

BUGS
       While  a	highly robust and time-tested scheduler, sched_4bsd lacks spe-
       cific knowledge of how  to  schedule  advantageously  in	 non-symmetric
       processor configurations, such as hyper-threading.

FreeBSD	14.3		       January 21, 2008			 SCHED_4BSD(4)

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<https://man.freebsd.org/cgi/man.cgi?query=sched_4bsd&sektion=4&manpath=FreeBSD+14.3-RELEASE+and+Ports>

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