xref: /freebsd/share/man/man4/sched_ule.4 (revision 38f0b757fd84d17d0fc24739a7cda160c4516d81)
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25.\" $FreeBSD$
26.\"
27.Dd August 10, 2012
28.Dt SCHED_ULE 4
29.Os
30.Sh NAME
31.Nm sched_ule
32.Nd ULE scheduler
33.Sh SYNOPSIS
34.Cd "options SCHED_ULE"
35.Sh DESCRIPTION
36The
37.Nm
38scheduler
39provides a number of advanced scheduler
40features not present in
41.Xr sched_4bsd 4 ,
42the traditional system scheduler.
43These features address SMP and interactivity and include:
44.Pp
45.Bl -bullet -compact -offset indent
46.It
47Thread CPU affinity.
48.It
49CPU topology awareness, including for hyper-threading.
50.It
51Per-CPU run queues.
52.It
53Interactivity heuristics that detect interactive applications and schedules
54them preferentially under high load.
55.El
56.Pp
57The following sysctls are relevant to the operation of
58.Nm :
59.Bl -tag -width indent
60.It Va kern.sched.name
61This read-only sysctl reports the name of the active scheduler.
62.It Va kern.sched.quantum
63This read-write sysctl reports or sets the length of the quantum (in
64micro-seconds) granted to a thread.
65.El
66.Sh SEE ALSO
67.Xr sched_4bsd 4 ,
68.Xr sysctl 8
69.Sh HISTORY
70The
71.Nm
72scheduler first appeared in
73.Fx 5.1 .
74.Sh AUTHORS
75.An Jeff Roberson
76.Aq jeff@FreeBSD.org
77