xref: /freebsd/share/man/man4/sched_ule.4 (revision 1e413cf93298b5b97441a21d9a50fdcd0ee9945e)
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25.\" $FreeBSD$
26.\"
27.Dd June 5, 2007
28.Os
29.Dt SCHED_ULE 4
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
39is an experimental scheduler that provides a number of advanced scheduler
40features not present in
41.Xr sched_4bsd 4 ,
42the default 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.El
63.Pp
64The
65.Nm
66scheduler
67is disabled by default as it is experimental.
68See the
69.Sx BUGS
70section for more information.
71.Sh SEE ALSO
72.Xr sched_4bsd 4 ,
73.Xr sysctl 8
74.Sh HISTORY
75The
76.Nm
77scheduler first appeared in
78.Fx 5.1 .
79.Sh AUTHORS
80.An Jeff Roberson
81.Aq jeff@FreeBSD.org
82